PT2E-3041

Gas Detector Head
GD-84D-EX Series
GD-84D-EX-EC
GD-84D-EX
GD-84D-EX-ET-EC
GD-84D-EX-ET
GD-84D-EX-EA-EC
GD-84D-EX-EA

Operating Manual

INDEX

INDEX
1.

2.

3.

4.

Product Overview ....................................................................................................................................... 6
1-1 Introduction .......................................................................................................................................... 6
1-2 Product intended use and features ...................................................................................................... 7
1-2-1 Communication systems by model and corresponding sensors .............................................. 7
1-2-2 Product features ....................................................................................................................... 7
1-3 DANGER, WARNING, and NOTE ....................................................................................................... 8
1-4 Checking CE/UKCA marking ............................................................................................................... 8
Important Safety Information ........................................................................................................................ 10
2-1 Danger information ............................................................................................................................ 10
2-2 Warning information ........................................................................................................................... 10
2-3 Caution information ............................................................................................................................ 11
Product Configuration .............................................................................................................................. 12
3-1 Main unit and accessories ................................................................................................................. 12
3-2 Part names and functions .................................................................................................................. 14
3-2-1 Main unit part names and functions ....................................................................................... 14
3-2-2 Front panel and LCD screen part names and functions ........................................................ 16
3-3 Block diagram .................................................................................................................................... 18
3-3-1 Electrical circuit diagram ........................................................................................................ 18
3-3-2 Piping diagram ....................................................................................................................... 21
Installation ................................................................................................................................................ 22
4-1 Installation precautions ...................................................................................................................... 22
4-2 System design precautions................................................................................................................ 23
4-3 Providing maintenance space............................................................................................................ 26
4-3-1 Maintenance space

ET .................................................................................................... 26

4-3-2 Maintenance space

4-20mA

EA ............................................................................ 28

4-4 Installing the main unit ....................................................................................................................... 30
4-4-1 Installing the main unit (without the mounting plate for compatibility with the GD-70D) ........ 31
4-4-2 Installing the main unit (using the mounting plate for compatibility with the GD-70D) ........... 34
4-5 Fitting sensors.................................................................................................................................... 38
4-5-1 Configuration of the main unit ................................................................................................ 38
4-5-2 Fitting sensors ........................................................................................................................ 40
4-6 Wiring procedure................................................................................................................................ 42
4-6-1 Recommended cables............................................................................................................ 42
4-6-2 Terminal plate specifications

5.

4-20mA

EA .............................................................. 43

4-6-3 Terminal plate connections ..................................................................................................... 44
4-6-4 Grounding terminal connections............................................................................................. 45
4-7 Pipe installation .................................................................................................................................. 47
Usage Instructions ................................................................................................................................... 49
5-1 Preparations for startup ..................................................................................................................... 49
5-2 Turning on the power ......................................................................................................................... 50
5-3 Basic operation flow ........................................................................................................................... 52
5-4 User mode ......................................................................................................................................... 54
5-4-1 User mode setting items......................................................................................................... 54
5-4-2 Switching to user mode .......................................................................................................... 55
5-5 Performing air calibration (AIR) ......................................................................................................... 56
5-6 Checking setting values (user mode) ................................................................................................ 58
5-6-1 Checking the alarm setpoints (CONFIRM)............................................................................. 58
5-6-2 Checking flow values (FLOW) ................................................................................................ 60

2 / 191

INDEX

5-6-3 Checking the version of the main unit (84D VER).................................................................. 61
5-6-4 Checking the sensor versions (SEN VER) ............................................................................. 62
5-6-5 Checking the communication PCB version (NET VER)
6.

EA ................................ 62

5-7 Shutting down .................................................................................................................................... 63
Alarm Activation ....................................................................................................................................... 64
6-1 Gas (oxygen) alarm pattern ............................................................................................................... 64
6-1-1 Alarm Activation ...................................................................................................................... 64
6-1-2 Contact operation (auto reset)

4-20mA

6-1-3 Contact operation (self-latching)

7.

ET

4-20mA

EA........................................................... 65

EA ........................................................ 66

6-1-4 Response when a gas alarm is triggered ............................................................................... 69
6-2 Fault alarm patterns ........................................................................................................................... 70
6-3 External output operations ................................................................................................................. 71
6-4 Various functions to ensure proper alarm activation.......................................................................... 74
6-4-1 Zero suppression function ...................................................................................................... 74
6-4-2 Zero follower function ............................................................................................................. 75
6-4-3 Sensitivity correction function ................................................................................................. 75
6-4-4 Calibration history, alarm trend history, and event history functions ...................................... 76
6-4-5 Automatic sensor recognition function ...................................................................................76
Maintenance............................................................................................................................................. 78
7-1 Maintenance intervals and maintenance items ................................................................................. 78
7-2 Performing alarm tests ....................................................................................................................... 80
7-3 Maintenance (regular maintenance) mode ........................................................................................ 82
7-3-1 Maintenance mode setting items ........................................................................................... 82
7-3-2 Switching to maintenance mode ............................................................................................ 83
7-4 Performing a gas introduction test ..................................................................................................... 85
7-5 Performing calibration ........................................................................................................................ 86
7-5-1 Running zero calibration......................................................................................................... 86
7-5-2 Running span adjustment....................................................................................................... 88
7-5-3 Connecting the calibration gas ............................................................................................... 91
7-5-4 Disconnecting the calibration gas .......................................................................................... 93
7-6 Adjusting the flow ............................................................................................................................... 94
7-6-1 Checking the flow (FLOW) ..................................................................................................... 94
7-6-2 Manually adjusting the flow (FLOW) ......................................................................................95
7-6-3 Correcting the flow value (DEF FLOW) .................................................................................. 96
7-7 Checking setting values (maintenance mode)................................................................................... 97
7-7-1 Checking the date last calibrated (LAST CAL)....................................................................... 97
7-7-2 Checking the set potential (E VOLT) ...................................................................................... 98
7-7-3 Checking the temperature of the detector (TEMP) ................................................................ 98
7-8 Setting the initial date of sensor use (S SET) .................................................................................... 99
7-9 Making changes in Environmental setting 1 ....................................................................................100
7-9-1 INHIBIT setting (INHIBIT) .....................................................................................................100
7-9-2 Alarm setpoints (ALM P).......................................................................................................102
7-9-3 Alarm delay time setting (ALM DLY).....................................................................................104
7-9-4 Fault alarm tests (F TEST) ...................................................................................................105
7-9-5 Terminal unit settings (OPT ACT)

4-20mA

EA .....................................................1077-10 Making changes in Environmental setting 2 ..................................................................................108
7-10-1 Date and time setting (DAY TIME) .....................................................................................109
7-10-2 Zero suppression value setting (SUPPRESS) ................................................................... 111
7-10-3 Zero suppression type setting (SUP TYPE) ....................................................................... 112
7-10-4 Settings for contacts during alarm tests (TEST RLY)

3 / 191

4-20mA

EA.................... 114

INDEX

7-10-5 Settings for external output during alarm tests (TEST4-20)
7-10-6 Energized/de-energized setting (RLY PTRN)

4-20mA

4-20mAEAEA.......... 115................................ 116

7-10-7 Alarm type setting (ALM TYPE).......................................................................................... 119
7-10-8 Alarm pattern setting (ALM PTRN) .....................................................................................121
7-10-9 Alarm value limiter setting (AL LIMIT) ................................................................................122
7-10-10 Fault pattern setting (FLT PTRN) .....................................................................................123
7-10-11 Flow automatic adjustment setting (AT FLOW) ................................................................124
7-10-12 Zero follower setting (ZERO)............................................................................................125
7-10-13 24-hour zero follower settings (ZERO 24F) .....................................................................126
7-10-14 Sensitivity correction settings (S ASSIST) .......................................................................128
7-10-15 External output in maintenance mode setting (MNT OUT)
7-10-16 External output adjustment (MA 4- 20)

4-20mA

EA

4-20mA

EA ..........129........................................131

7-10-17 Backlight setting (BK LIGHT) ...........................................................................................132
7-10-18 ETHERNET settings (ETHERNET)ETEA........................................................133

7-10-19 Pump drive level diagnostic settings (PUMP CK) ............................................................136
7-10-20 Setting for the behavior of fault contacts when flow is low (FLT RLY)

4-20mA

EA .................................................................................................................................137
7-10-21 External output during fault setting (FLT OUT)

4-20mA

EA ............................138

7-10-22 Caution display setting (CAU DISP) .................................................................................139
7-10-23 Caution output setting (CAU OUT) ...................................................................................141
7-10-24 Displayed gas name setting (GAS NAME).......................................................................142
7-10-25 LCD contrast adjustment (CONTRAST) ..........................................................................144
8. Replacing and cleaning parts ................................................................................................................. 145
8-1 Replacing consumable parts ...........................................................................................................145
8-1-1 Replacing sensors ................................................................................................................145
8-1-2 Dust filter replacement .........................................................................................................150
8-2 Replacing periodic replacement parts .............................................................................................151
8-2-1 List of recommended periodic replacement parts ................................................................151
8-2-2 Pump unit replacement ........................................................................................................151
8-2-3 Flow sensor unit replacement ..............................................................................................153
8-2-4 Fan unit replacement............................................................................................................156
8-3 Cleaning this product .......................................................................................................................158
9. Storage, Relocation, and Disposal......................................................................................................... 159
9-1 Procedures for storage or when not used for extended periods .....................................................159
9-2 Relocation or reuse ..........................................................................................................................160
9-3 Product disposal ..............................................................................................................................160
10. Troubleshooting ..................................................................................................................................... 161
10-1 Product abnormalities ....................................................................................................................161
10-2 Reading abnormalities ...................................................................................................................165
11. Product Specifications ........................................................................................................................... 166
11-1 GD-84D-EX Specifications .............................................................................................................166
11-1-1 GD-84D-EX-EC ..................................................................................................................166
11-1-2 GD-84D-EX.........................................................................................................................168
11-1-3 GD-84D-EX-ET-EC .............................................................................................................170
11-1-4 GD-84D-EX-ET ...................................................................................................................172
11-1-5 GD-84D-EX-EA-EC ............................................................................................................174
11-1-6 GD-84D-EX-EA...................................................................................................................176
4 / 191

INDEX

11-2 Sensor specifications .....................................................................................................................178
11-2-1 Electrochemical type ..........................................................................................................178
11-2-2 New ceramic type ...............................................................................................................179
11-2-3 Semiconductor type ............................................................................................................180
11-2-4 Hot-wire semiconductor type ..............................................................................................182
12. Appendix ................................................................................................................................................ 184
12-1 Detection principle .........................................................................................................................184
12-1-1 Electrochemical type ..........................................................................................................184
12-1-2 New ceramic type ...............................................................................................................186
12-1-3 Semiconductor type............................................................................................................188
12-1-4 Hot wire semiconductor type ..............................................................................................190
12-2 Terminology....................................................................................................................................191

5 / 191

1. Product Overview

1-1 Introduction

1

Product Overview
1-1 Introduction
Thank you for purchasing this GD-84D-EX series Gas Detector ("product" hereinafter).
This operating manual describes product operating procedures and specifications. The manual provides
information essential to the correct use of the product.
Make sure you have read and fully understood the contents of this manual before using the product.
Keep this operating manual on hand to allow ready reference during use.
The contents of this manual are subject to change without notice to allow product improvements. Any
duplication or reproduction of this manual without permission is prohibited, whether in whole or in part.
Riken Keiki accepts no liability for accidents or damage resulting from use of the product, whether within or
outside the warranty period.
Review the warranty policy indicated on the warranty.
Before using the product, please confirm that the model of the product you purchased matches the modelof the product covered by this operating manual.

<Models covered by this operating manual> GD-84D-EX-EC
 GD-84D-EX
 GD-84D-EX-ET-EC
 GD-84D-EX-ET GD-84D-EX-EA-EC
 GD-84D-EX-EA<This operating manual>
Where descriptions differ for different product models, this operating manual uses the following icons toindicate each model:
GD-84D-EX-EC
GD-84D-EX

4 - 20 mA models

4-20mA

GD-84D-EX-ET-EC
GD-84D-EX-ET

ET modelsET

GD-84D-EX-EA-EC
GD-84D-EX-EA

EA models

EA

Operating procedures and specifications for which no icons appear apply to all models.

6 / 191

1. Product Overview

1-2 Product intended use and features

1-2 Product intended use and features
This product is a fixed multi-gas detector head that detects leaks of various gases used in semiconductor
factories and similar locations.
It detects combustible gases and toxic gases in the surrounding atmosphere and activates alarms if preset
concentrations are exceeded.
Gas alarms are safety devices. They are not gas concentration meters nor gas analyzers designed toanalyze or measure gas quality or gas volumes.
Use the device correctly after confirming you understand the product’s features and characteristics.

1-2-1 Communication systems by model and corresponding sensors
This line of products features various models incorporating the following communication systems andcorresponding sensors.
Check the specifications before use to confirm the correct gases will be detected in accordance with theintended purpose.
Communication
methodCorresponding
sensor

GD-84D-EX-EC

4 - 20 mA

GD-84D-EX

4 - 20 mA

GD-84D-EX-ET-EC

Ethernet

GD-84D-EX-ET

Ethernet

ESF
NCF, SGF, SHF,
ESF
ESF
NCF, SGF, SHF,
ESF

Model

GD-84D-EX-EA-EC
GD-84D-EX-EA

Ethernet
4 - 20 mA
Ethernet
4 - 20 mA

Power source
24 V DC○

PoE+○

Contact output
Alarm
○

Fault
○

○

○

○
○

ESF

○*

○*

○

○

NCF, SGF, SHF,
ESF

○*

○*

○

○

* Do not use a 24 V DC power supply and PoE+ at the same time.

<Sensor models and detection principles>
Sensor model

Detection principle

NCF

New ceramic type

SGF

Semiconductor type

SHF

Hot-wire semiconductor
type

ESF

Electrochemical type1-2-2 Product features
 This product incorporates gas sensors that detect leaking combustible and/or toxic gases or oxygen
deficiency.
 The detected gas concentration is displayed on a full-dot LCD.
 This product incorporates a pump to draw in gas and perform gas detection.
 The product can be equipped with up to four sensors to detect up to four gas types.

7 / 191

1. Product Overview

1-3 DANGER, WARNING, and NOTE

1-3 DANGER, WARNING, and NOTEThis operating manual uses the following categories to indicate potential damage/hazards if the user
disregards the information provided and uses the product incorrectly:

DANGER

This indicates situations in which improper handling may result in fatal or
serious injury or significant property damage.

WARNING

This indicates situations in which improper handling may result in serious
injury or significant property damage.

CAUTION

This indicates situations in which improper handling may result in minor injury
or minor property damage.

Additionally, usage recommendations are indicated as follows:

NOTE

This indicates items that will be helpful to know when using the product.

1-4 Checking CE/UKCA marking
CE/UKCA marking compliant models will feature CE/UKCA marking labels. Check actual productspecifications before use.
Before using products with CE/UKCA marking, please refer to the “Declaration of Conformity” provided at
the end of this manual.
The CE/UKCA marking is found on the nameplate affixed to the rear of the front cover.

CE/UKCA marking

Location of CE/UKCA marking(Rear of front cover)8 / 191

2. Important Safety Information

2-1 Danger information

2

Important Safety Information
2-1 Danger information
DANGER The product is a non-explosion-proof device. Never attempt to use the product to detect gases
above the lower explosive limit (LEL).

2-2 Warning information
WARNING
Power source Before turning on the power for the product, be sure to confirm that the power source meets the
specified voltage requirements. Avoid using unstable power sources; doing so may lead tomalfunctions.
Protective grounding required Do not cut the protective grounding cable of the product or disconnect the protective grounding
terminal.
Defects of protective functions
 Before operating the product, check the protective functions for defects.
Do not turn on the product if you suspect any problems with the protective grounding and otherprotective functions.
External connections
 Be sure to provide secure protective grounding before connecting the product to the detection target
or external control circuit.
Pipes
 Avoid applying excessive pressure to the product’s sampling pipe openings.
This product is designed to perform gas detection by drawing in gas at atmospheric pressure.
Applying excessive pressure to the product’s sampling pipe openings (GAS IN, GAS OUT) is
dangerous. Doing so may cause the detection target gas to leak from the product.
 Discharge exhaust gas after detection to a location confirmed to be safe by connecting an exhaust
pipe to the detection target gas outlet (GAS OUT) located on the bottom of the main unit.
Sensor handling Never disassemble the sensor.
Electrochemical type sensors (ESF) contain electrolyte. Contact with electrolyte may result in skininflammation. Contact with eyes may result in blindness. Contact with clothing may result in
discoloration or damage to the fabric.
If contact occurs, rinse the area immediately with water.
Zero calibration in surrounding atmosphere (air calibration)
 Check the atmosphere for freshness before performing zero calibration in the surrounding
atmosphere (air calibration for oxygen deficiency alarm models). Proper calibration is not possible in
the presence of interference gases. The presence of interference gases is also extremely
dangerous because the product may not detect actual gas leaks correctly.
9 / 191

2. Important Safety Information

2-3 Caution information

Operating in an environment with gases Do not operate this product in locations where combustible or explosive gases or vapor are present.
Operating this product in such environments is extremely hazardous.
Action when a gas alarm occurs
 A gas alarm indicates the presence of extreme danger. The user must take appropriate action after
taking appropriate steps to ensure safety.
 Depending on the type of gas detected, the sensor characteristics may be severely degraded. If thegas alarm is triggered, we recommend performing maintenance on all sensors fitted to this productto check their gas sensitivity.

2-3 Caution information
CAUTION
Do not use walkie-talkies near the product.
 Radio waves from walkie-talkies or other radio transmitting devices near the product or cables may
affect readings. Use walkie-talkies or similar devices only in locations where they will not affectproduct functions.
Wait at least five seconds after turning off the power before turning the power back on.
 The product may not function correctly if the power is turned on again within five seconds.
Confirm that the flow display is the stipulated flow before using the product.
 If the flow display is not the stipulated flow, gas will not be detected properly. Check whether theflow is unstable or absent.
Attach a dust filter.
 Attach the specified filters when using this product to avoid the effects of gas absorption andairborne dust.
The correct dust filter type depends on the type of gas to be detected. Contact our sales department
for more information.
Observe the specified operating range to avoid condensation in the pipes.
 Condensation within the pipes may lead to gas adsorption, blockages, and other problems thatmake it impossible to detect gases accurately. To prevent condensation within the pipes, carefully
monitor temperature and humidity both at the sampling point and within the general environment.
When detecting gases that become more corrosive when dissolved in water (e.g., highly acidic
gases), note that consequences may include impaired capacity to detect gases and corrosive
damage to internal parts.
Do not use external output from the product to control other devices.
 The product is not a control device. Never attempt to use the external output of the product tocontrol other devices.
Do not disassemble or modify the product or alter the settings unless absolutely necessary.
 Product performance cannot be guaranteed if the product is disassembled or modified. Additionally,
altering the settings unnecessarily without a proper understanding of the details may prevent thealarm from operating correctly.
Read this operating manual carefully to ensure correct use of the product.
Be sure to perform regular maintenance.
 The product is a safety device. Maintain the product periodically to ensure safety. Continuing to use
the product without adequate maintenance will result in sensor sensitivity variations, preventing
accurate gas detection.

10 / 191

3. Product Configuration

3-1 Main unit and accessories

3

Product Configuration
3-1 Main unit and accessories
Open the box and packaging and inspect the main unit and accessories.
If any accessories are missing, contact our sales department.

<ET models>Standard accessories
Main unit

Protective rubber
caps*1(2)

Dust filter*2(1)

Operating
Manual(1)*1 These caps protect the GAS IN and GAS OUT ports. Remove them when the product is in use.
*2 One dust filter is supplied. The dust filter supplied depends on the model.

Optional accessories
Mounting plate for compatibility with GD-70D(to use with four mounting screws)

Mounting plate for compatibility with GD-70D(for use with three or four mounting screws)

11 / 191

3. Product Configuration

3-1 Main unit and accessories<4 - 20 mA models, EA models>Standard accessories
Main unit

Protective
rubbercaps*1(2)

Dust filter*2(1)

Terminal unit

Operating manual (1)*1 These caps protect the GAS IN and GAS OUT ports. Remove them when the product is in use.
*2 One dust filter is supplied. The dust filter supplied depends on the model.

Optional accessories
Mounting plate for compatibility with GD-70D(for use with four mounting screws)

Mounting plate for compatibility with GD-70D(for use with three or four mounting screws)

12 / 191

3. Product Configuration

3-2 Part names and functions

3-2 Part names and functions
3-2-1 Main unit part names and functions<Front of main unit>
①

②
③

④

No.

Name

Function①

Fan

This is the cooling fan.
GD-84D-EX-EC, GD-84D-EX-ET-EC, and GD-84D-EX-EA-EC lack
fans.

②

Front panel

The LCD display and keys used to operate the product are located on
this panel.

③

LCD screen

Full-dot LCD screen that displays gas concentration and otherinformation④

Front coverThis cover protects the units inside the main unit.

13 / 191

3. Product Configuration

3-2 Part names and functions<Underside of main unit><4 - 20 mA models>

①

②

No.

④ ⑤

<ET models>① ②③<EA models>

④ ⑤

Name

①

②

③

Function①

GAS IN

This is the sampling pipe opening on the IN side.

②

Power switch

Power ON/OFF switch.

③

Ethernet cable connection
inlet

RJ-45 connector for connecting Ethernet cable④

Grounding terminal

Grounding wires are connected to this terminal.

⑤

GAS OUTThis is the sampling pipe opening on the OUT side.

14 / 191④ ⑤

3. Product Configuration

3-2 Part names and functions

3-2-2 Front panel and LCD screen part names and functions⑩① ② ③ ④

⑪

⑫

⑬

⑤
⑭
⑮

⑥

⑦
⑧
⑨

⑯
⑱

GD-84D-EX

⑰

No.

Name

Function①

Power LED (POWER)

This is the power LED. Lights up (green) when the power is ON.

②

Alarm lamp (ALM1)

This is the ALM1 (first alarm) alarm lamp. This lights up (red) when thealarm setpoint for ALM1 (first alarm) is reached.

③

Alarm lamp (ALM2)

This is the ALM2 (second alarm) alarm lamp. This lights up (red) when
the alarm setpoint for ALM2 (second alarm) is reached.

④

Fault lamp (FAULT)This is the Fault lamp. This lights up (yellow) when there is anabnormality with the product.

⑤

MODE key

Hold down in detection mode to switch to user mode.
In user mode or maintenance mode, this key is used to cancel settings
and to return to the previous screen.
Hold down this key in user mode or maintenance mode to return todetection mode.

⑥

▲ key

Used to select sensors or adjust values (UP)

⑦

▼ key

Used to select sensors or adjust values (DOWN)⑧

TEST/SET key

Hold down in detection mode to switch to the mode used to perform
alarm tests.
This key is used in various modes to confirm values or make settings.

⑨

SHIFT key

This key is used for supplementary functions in various modes.

⑩

Sensor positioning
indicators

These indicate the positions of the sensors.
Sensors [A1] and [A2] are fitted in flow passage A. Sensors [B1] and [B2]are fitted in flow passage B. (Refer to ‘4-5-1 Configuration of the mainunit’.)⑪

Gas name displayed

Displays the name of the detection target gas by chemical formula.
This can be changed to suit the fitted sensors. (Refer to‘7-10-24 Displayed gas name setting (GAS NAME)’.)⑫

Concentration display

Displays the gas concentration and other information.

⑬

Concentration bar
display

The segmented detection range (full scale) displays gas concentrations
as bars. It indicates concentrations as ratios of the full scale.

15 / 191

3. Product Configuration

3-2 Part names and functions⑭

Second alarm setpoint
displayThis indicates in points the second alarm setpoint as a ratio of the fullscale.

⑮

First alarm setpoint
displayThis indicates in points the first alarm setpoint as a ratio of the full scale.

⑯

Units display

Displays units matching sensor specifications (ppm, ppb, vol%, %, %LEL).

⑰

Maintenance display
sectionSetting details are displayed in user mode and maintenance mode.
Alarm contacts are disabled when [MAINTE] is displayed.

⑱

Flow display

Indicates the suction flow rate. The suction is 0.6 L/min (standard flowrate) when the suction flow rate indicator bar is positioned in the middle.

* The screen display examples used in this operating manual show H2, NH3, and CH4 as example detection target
gases.

<About the communication indicators> ET

EA

Icons on the maintenance display section indicate whether the product is transmitting or receiving whendata is being transmitted or received to/from upstream devices.

Icons indicating the productis transmitting or receiving

NOTE
 The suction flow rate for this product is automatically adjusted by the automatic flow adjuster
function. The flow rate is automatically adjusted even if the flow display varies from the stipulated
flow rate. No flow adjustment is normally required. Messages indicating [FLOW] (flow instability) or[E-05] (flow abnormality) are displayed if pipe blockages, leaks, or other factors prevent automatic
adjustment. If this happens, identify the cause, then adjust manually until the flow reaches the
stipulated value. (Refer to ‘7-6-2 Manually adjusting the flow (FLOW)’.)

16 / 191

3. Product Configuration

3-3 Block diagram

3-3 Block diagram
3-3-1 Electrical circuit diagram
Refer to the product electrical circuit diagram provided below.

<4 - 20 mA models>
Display (LCD)

Power supply section・ 24 V DC

Display (LED)・ POWER・ ALM1

Power source voltage
conversion section

・ ALM2
・ FAULT

Pump control circuit
Button panel
Control unit
CPU
Pump

Flow sensor

・ MODE・ TEST/SET・ ▲・ ▼・ SHIFT

Alarm contact control unit
・ Gas alarm contacts(Ch1 - 4 ALM1)
・ Gas alarm contacts(Ch1 - 4 ALM2)
・ Fault alarm contact(FAULT)* Standard settings forcontact operation
Under normal conditions:
De-energized
At an alarm state:
Energized

Sensors (Ch1 - 4)External output section
・ 4 - 20 mA

17 / 191

3. Product Configuration

3-3 Block diagram<ET models>Power supply section

Display (LCD)

・ PoE+

Display (LED)・ POWERPower source voltage
conversion section

・ ALM1
・ ALM2
・ FAULT

Transmitter

Control unit
CPU・ Ethernet

Button panel
・ MODE・ TEST/SET・ ▲Pump control circuit・ ▼・ SHIFT
Pump

Sensors (Ch1 - 4)

Flow sensor

18 / 191

3. Product Configuration

3-3 Block diagram<EA models>
Display (LCD)

Power supply section*
・ 24 V DC

Display (LED)・ PoE+

・ POWER・ ALM1
・ ALM2

Power source voltage
conversion section

・ FAULT

Transmitter

Button panel

・ Ethernet

・ MODE・ TEST/SET

Pump control circuitControl unit

・ ▲

CPU

・ ▼
・ SHIFT

Pump

Sensors (Ch1 - 4)

Flow sensor

Alarm contact control unit

External output section

・ Gas alarm contacts(Ch1 - 4 ALM1)
・ Gas alarm contacts(Ch1 - 4 ALM2)
・ Fault alarm contact(FAULT)* Standard settings forcontact operation
Under normal conditions:
De-energized
At an alarm state:
Energized

・ 4 - 20 mA* Do not use a 24 V DC power supply and PoE+ at the same time.

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3. Product Configuration

3-3 Block diagram

3-3-2 Piping diagram
Refer to the product piping circuit diagram provided below.

Flow monitor
SensorFlow
SensorPump

Flow automatic
adjustment

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4. Installation

4-1 Installation precautions

4

Installation
4-1 Installation precautions
Be sure to observe the following precautions when performing installation tasks.
Failure to observe these precautions may result in product failure and/or inability to detect gas correctly.

CAUTION The product is a precision device. The expected performance of this product may be affected by thelocation (environment) in which it is installed. Assess conditions at the installation location and takeappropriate measures.
 The product plays a key role in safety and disaster prevention. Install the required number of
products at appropriate locations to ensure efficacy.
 Areas where gas is likely to leak or accumulate may differ depending on the specific gas and thespecifics of the work spaces. Install products after duly considering the location and number ofunits.

<Do not install in locations subject to vibration or impact>
The product contains precision electronic components. Install the product in a stable location not exposed
to vibration, impact, or risk of falling.

<Do not install in locations exposed to water, oil, or chemicals>
Avoid installing in locations associated with risk of splashing water, oil, chemicals, or other liquids.

<Do not install in locations where temperatures can fall below -10 °C or exceed
40 °C>The product is designed for use in environments with ambient temperatures between -10 °C and 40 °C.
Install in a location where temperatures will not exceed the operating temperature range.

<Do not install in locations exposed to direct sunlight or sudden temperaturefluctuations>
Avoid installing in locations subject to direct sunlight or radiant heat (infrared radiation from hightemperature bodies) or in locations subject to sudden temperature changes.
Condensation may form inside the product, or the product may be unable to adjust to sudden temperaturefluctuations.

<Install away from noise-emitting devices (main unit and cables)>Install away from locations where high-frequency or high-voltage devices are present.
The product may be affected by electromagnetic noise, etc.

<Do not install in locations where maintenance is hazardous or not possible>
The product requires regular maintenance.
Do not install in the following or similar locations where maintenance is hazardous or not possible: Within systems where the system must be stopped for maintenance Locations where part of the system must be detached to allow maintenance Locations where the product cannot be removed due to the presence of pipes or racks
 Locations where maintenance work is hazardous: for example, near high-voltage cables

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4. Installation

4-2 System design precautions<Do not install in improperly grounded systems>
When installing within a system chassis, make sure the system is properly grounded to Class D orequivalent.

<Do not install in the presence of interference gases>
Do not install the product in locations where miscellaneous gases are present.

<Do not use cleaning products when cleaning this product>
When cleaning this product, do not use cleaning products.

4-2 System design precautions
CAUTION
 Unstable power sources or noise may result in malfunctions or false alarms.
 When designing systems based on or incorporating this product, be sure to incorporate theinformation provided on this page and in the ‘System Construction Manual’.

<Use of a stable power source>
The product’s external output and alarm contacts may activate while the system stabilizes at power-on orin the event of an instantaneous power failure. If you do not want the external output and alarm contacts toactivate, use a UPS (uninterruptible power system) or take appropriate measures on the receiving end.
Supply this product with the following power sources:
Power source
voltage4 - 20 mA models : 24 V DC ± 10 % (main unit terminal voltage)
ET models: PoE+ connection
EA models: 24 V DC ± 10 % (voltage of main unit terminal) or PoE+
connection (not to be supplied simultaneously)

Time allowed for
instantaneous
power failures

Up to approx. 10 ms*

Example of countermeasure:
Deploy an external UPS (uninterruptible
power system)or similar to guarantee
continuous operation and functionality.

Miscellaneous

Do not use with power sources
subject to very high power loads orhigh frequency noise.

Example of countermeasure:
Where necessary, use a line filter or otherdevice. Keep the product away from noise
sources.

* To recover from an instantaneous power failure exceeding 10 ms, restart the product.

<Design accounting for heat dissipation>
If you plan to install the product in a closed instrument panel or similar space, install ventilation fans at the
top and bottom of the panel.
Install the fans so that the temperature inside the instrument panel remains below 40 °C. Account for theheat produced by the unit itself.

<Lightning protection>
In factories or plants where cabling is configured as follows, damage may result in the event of lightning
strikes. The cables connected to the product may function as receiving antennas for the lightning: When cables are installed outdoors
 When cables are installed in the same duct as cables supplied from outside
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4. Installation

4-2 System design precautions

Lightning strikes may damage devices connected to the cable. Additionally, note that inductive lightning
surges due to lightning strikes cannot be entirely prevented, even if cables are installed in metal ducts orburied underground. While it is not possible to completely protect against disasters caused by lightning,
the following protective measures are available:<Protection against lightning>
Take appropriate measures based on environmental conditions and the importance of the facility.
 Passing the signal transmission path through optical fiber, etc.
 Protection using a lightning arrester (cable safety retainer)
A lightning arrester (cable safety retainer) can be installed before the field devices and central processing
equipment to safeguard against inductive lightning surges transmitted through the cable. For information
on how to use lightning arresters, please contact the manufacturer.
<Grounding>
Surge noise is caused by lightning strikes and other factors. This product must be grounded to protect
against these factors.

NOTE
 Lightning arresters include circuits to remove surge voltages that may damage field devices. For
this reason, installing a lightning arrester can attenuate signals.
Perform an operation check before installing lightning arresters. Additionally, lightning arresters
cannot remove all surge voltages.

<Using alarm contacts correctly>
The alarm contacts on this product are designed to transmit signals to activate external buzzers, alarmindicators, revolving lights, etc.
Do not use for control purposes (e.g., controlling shutoff valves).

CAUTION When relay contacts are to be left in a constantly closed state, burning may occur at the contacts
with minimal vibration.
 A de-energized b contact (break contact) may cause a momentary open operation due to external
forces or other physical impact.
 If a b contact is used as an alarm contact, implement measures to account for such momentary
operations—for example, add a delay operation (of approximately 1 second) to the signal on the bcontact receiving side.
The alarm contact specifications of the product assume resistance loads. If the alarm contacts use
inductive loads, a counter‐electromotive force will occur at the contacts, leading to the following potential
problems:
 Relay contact welding, insulation failure, contact failure Damage to electrical components due to high voltages occurring inside the product Malfunctions due to CPU runaway

CAUTION As a rule, do not use the alarm contacts of the product to operate inductive loads. In particular,
never use to operate devices like fluorescent lamps and motors.
 If operating inductive loads, link using an external relay (contact amplification). However, since theexternal relay coil also constitutes an inductive load, use a relay that runs on low voltage (within
100 V AC) and a suitable surge protector (CR circuit, etc.) to protect the contacts of this product.

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4. Installation

4-2 System design precautions

When operating a load, stabilize the operation of this product, then take the following measures, whereappropriate, to protect the alarm contacts.
 Link the circuits (contact amplification) using an external relay (not exceeding 24 V DC). Add a surge
absorber (SK1) appropriate for the rating to the external relay.
 Where necessary, add a surge absorber (SK2) to the load side of the external relay.
 In certain cases, due to load conditions, it may be preferable to attach the surge absorber to the contact
side. Confirm load behavior and determine the optimal attachment point.
<On GD-84D-EX>
External relay

SK2

Load

Coil

SK1
Alarm contact* SK1, SK2: Surge absorbers

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4. Installation

4-3 Providing maintenance space

4-3 Providing maintenance space
When installing the product, make sure there is space for maintenance.

4-3-1 Maintenance spaceET<When installing one unit of this product>
300

170
30

150
(Unit: mm)<When installing this product in series><When not using the mounting plate for compatibility with the GD-70D>
Maintenance space

Maintenance space

Maintenance space(Unit: mm)

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4. Installation

4-3 Providing maintenance space<When using the mounting plate for compatibility with the GD-70D>• When GD-70D is installed at a pitch of 5 mm
Fixed at 2 points either
inside or outside
Maintenance space

Maintenance space

Maintenance space

Use of mounting platefor 5mm pitch

Use of mounting platefor 5mm pitch

Use of mounting platefor 5mm pitch(Unit: mm)• When GD-70D is installed at a pitch of 10 mm
Fixed at 2 points either
inside or outside
Maintenance space

Maintenance space

Maintenance space

Use of mounting platefor 5mmUse of mounting platefor 5mmUse of mounting platefor 5mm(Unit: mm)• When securing with three points as with GD-70D

Maintenance space

Maintenance space

Maintenance space(Unit: mm)

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4. Installation

4-3 Providing maintenance space

CAUTION We recommend installing at a minimum pitch of 10 mm. Make this a minimum of 10 mm.
If a wall is located either to the left or right end of the installed series of devices, leave 10 mm ormore between the wall and the left or right end of the installed devices.
 To install the product in series, install on a rack or wall to protect against vibrations.
If the rack or wall on which the products are installed lacks sufficient strength, the vibration of thebuilt-in pumps may generate resonance between the products. If this occurs, take appropriate
measures―for example, reinforcing the rack or wall.

4-3-2 Maintenance space

4-20mA

EA<When installing one unit of this product>
170

300
30

150
(Unit: mm)<When installing this product in series><When not using the mounting plate for compatibility with the GD-70D>
Maintenance space

Maintenance space

Maintenance space(Unit: mm)

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4. Installation

4-3 Providing maintenance space<When using the mounting plate for compatibility with the GD-70D>• When GD-70D is installed at a pitch of 5 mm
Fixed at 2 points either
inside or outside
Maintenance space

Maintenance space

Maintenance space

Use of mounting platefor 5mm pitch

Use of mounting platefor 5mm pitch

Use of mounting platefor 5mm pitch(Unit: mm)• When GD-70D is installed at a pitch of 10 mm
Fixed at 2 points either
inside or outside
Maintenance space

Maintenance space

Maintenance space

Use of mounting platefor 5mmUse of mounting platefor 5mmUse of mounting platefor 5mm(Unit: mm)• When securing with three points as with GD-70D

Maintenance space

Maintenance space

Maintenance space(Unit: mm)

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4. Installation

4-4 Installing the main unit

CAUTION We recommend installing at a minimum pitch of 10 mm. Make this a minimum of 10 mm.
If a wall is located either to the left or right end of the installed series of devices, leave 10 mm ormore between the wall and the left or right end of the installed devices.
 To install the product in series, install on a rack or wall to protect against vibrations.
If the rack or wall on which the products are installed lacks sufficient strength, the vibration of thebuilt-in pumps may generate resonance between the products. If this occurs, take appropriate
measures; for example, reinforcing the rack or wall.

4-4 Installing the main unit
CAUTION For performance reasons, this product must be installed facing in a particular direction. Install the
product horizontally as shown in the figure below. Keep the product oriented horizontally as shownin the figure below when carrying, temporarily removing, or relocating the product.
<Wall mounting><Ceiling mounting>

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4. Installation

4-4 Installing the main unit

4-4-1 Installing the main unit (without the mounting plate for compatibility
with the GD-70D)

CAUTION Before installing this product, remove the protective rubber caps fitted to GAS IN and GAS OUT.
If the product is installed with the rubber caps still attached, excess loads will be imposed on thepumps and sensors when the power is turned ON. This may result in damage.

<ET models>1

Place the main unit against the installation surface andsecure with two screws.
We recommend double SEMS screws (M4-14).

2

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther down to open to 180°.

3

Use two screws to secure the main unit to theinstallation surface.

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Projection on
the top

4. Installation

4-4 Installing the main unit

<4 - 20 mA models, EA models>1

Place the terminal unit against the installation surface
and secure with four screws.

2

Mount the main unit to the terminal unit.

3

Pull the projection on the top of the main unit towards
you to open the front cover.
The front cover opens to approximately 120°. Push further
down to open to 180°.

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Projection on
the top

4. Installation

4-4 Installing the main unit

4

Use four screws to secure the main unit to theterminal unit.

5

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

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4. Installation

4-4 Installing the main unit

4-4-2 Installing the main unit (using the mounting plate for compatibility with
the GD-70D)

CAUTION Install so that there is no gap between the mounting plate for compatibility with the GD-70D and thesurface on which it is installed.
A gap may result in unnecessary vibrations and noise.
 Before installing this product, remove the protective rubber caps fitted to GAS IN and GAS OUT.
If the product is installed with the rubber caps still attached, excess loads will be imposed on thepumps and sensors when the power is turned ON. This may result in damage.

<ET models>1

Use four double SEMS screws (M4/M5)
to secure the mounting plate forcompatibility with the GD-70D to theinstallation surface.
You can also use three double SEMS
screws (M4/M5) when using themounting plate for compatibility with the
GD-70D for three or four mounting
screws.
The following screws are recommended
for mounting:・ Screw type: double SEMS M4 or M5
・ Screw length: 8 mm or more

<Securing with four double SEMS screws>

Mounting plate for four
mounting screws

When securing with three double SEMS
screws, use the mounting plate for threeor four mounting screws. You cannot use
the mounting plate for four mounting
screws.

Mounting plate for three or four
mounting screws<Securing with three double SEMS screws>

Mounting plate for three orfour mounting screws

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4. Installation

4-4 Installing the main unit

2

Mount the main unit on the mounting plate forcompatibility with the GD-70D.

3

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther down to open to 180°.

4

Use four screws to secure the main unit to themounting plate for compatibility with the
GD-70D.

5

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

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Projection on
the top

4. Installation

4-4 Installing the main unit

<4 - 20 mA models, EA models>1

Use four double SEMS screws (M4/M5)
to secure the mounting plate to theinstallation surface (for compatibility
with the GD-70D).
You can also use three double SEMS
screws (M4/M5) when using themounting plate for compatibility with the
GD-70D for three or four mounting
screws.
The following screws are recommended
for mounting:・ Screw type: double SEMS M4 or M5
・ Screw length: 8 mm or more

<Securing with four double SEMS screws>

Mounting plate for four
mounting screws

Mounting plate for three or four
mounting screws<Securing with three double SEMS screws>

When securing with three double SEMS
screws, use the mounting plate for threeor four mounting screws. You cannot use
the mounting plate for four mounting
screws.

Mounting plate for three or four
mounting screws

2

Use four screws (M4) to secure the terminal unit to
the mounting plate for compatibility with the GD-70D.
Use the supplied screws.
・ Screw type: M4
・ Screw length: 6 mm

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4. Installation

4-4 Installing the main unit

3

Mount the main unit to the terminal unit.

4

Pull the projection on the top of the main unit towards
you to open the front cover.
The front cover opens to approximately 120°. Push further
down to open to 180°.

5

Use the four screws to secure the main unit to
the terminal unit.

6

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

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Projection on
the top

4. Installation

4-5 Fitting sensors

4-5 Fitting sensors
4-5-1 Configuration of the main unit
Fan unit
Pump unit

Flow sensor unit

SensorChamber unit

CAUTION Each unit is composed of precision components. In particular, be careful to avoid dropping thesensors when removing them. Dropping or exposing to strong impact can cause sensors or units tomalfunction. Dropping or exposing to strong impact may also impair sensor performance.

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4. Installation

4-5 Fitting sensors<Sensor positioning>
Up to four sensors can be fitted in this product.
The two passages on the left belong to the A side. The two on the right belong to the B side.
The positions for the sensors are [A2] [A1] [B1] [B2], in order from left. These correspond to the [A2] [A1]
[B1] [B2] on the LCD screen.
Sensor fitted to [A1]
Sensor fitted to [A2]

Sensor fitted to [B2]
A2

A1

Flow
passage A

B1

B2

Sensor fitted to [B1]Flowpassage B<Sensor handling>
Whatever the detection principle, all sensors fitted to the product have the same shape. It is also possible
to swap sensors (excluding the D-84D-EX-EC, GD-84D-EX-ET-EC, and GD-84D-EX-EA-EC).
However, certain restrictions apply to sensor combinations.
The handling of each of the sensors depends on the operating principles in question. Contact our sales
department or sales office for more information.

CAUTION From a quality and safety standpoint, handle the sensors used in these products with care.
Sensor storage requires setting aside a storage compartment specifically for the sensors, including
facilities for supplying power. As a rule, avoid handling or storing the sensors after removing themfrom the product. Contact Riken Keiki to handle sensor disposal.
 Take particular care not to fit the sensors incorrectly.
[C-02] is displayed on the LCD when a sensor is fitted that uses a different principle or has different
specifications from those at the time of shipping. If [C-02] is displayed, check the sensor
specifications.
 Perform calibration (zero calibration, span adjustment) after sensor replacement.

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4. Installation

4-5 Fitting sensors

4-5-2 Fitting sensors
1

Pull the projection on the top of the main
unit towards you to open the front cover.
The front cover opens to approximately 120°.
Push further down to open to 180°.

2

Loosen the four white knurled screws on thechamber unit.

3

Grasp the projections on the left and right ofthe chamber unit. Pull towards you, thenlower to open.

Chamber unit
projection

4

Attach the sensor.
Grasp the cylindrical part of the sensor. Match theface of the connector on the main unit and theconnector on the sensor, then push in firmly to secure
into place.
Avoid pressing on the top of the sensor while doing
this. Doing so may damage sensor.
Top of sensor

Chamber unit

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Chamber unit
projection

4. Installation

4-5 Fitting sensors

5

Return the chamber unit to its original position.

6

Tighten the four white knurled screws on thechamber unit.
Tighten the knurled screws so that the chamber unit issecured in place.
Gas leaks may result if the knurled screws are nottightened properly.

7

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

CAUTION To attach the sensor to the main unit, push the sensor connector in firmly so that it is secured inplace. Improper attachment may cause the sensor to fall out and damage the connector.

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4. Installation

4-6 Wiring procedure

4-6 Wiring procedure
CAUTION Take care to avoid damaging internal electronic circuits during wiring work. Additionally, avoid
excessive cable weights or cable routing that may generate excessive stress.
 Do not route the power cable and signal cable alongside power lines for motors or similarequipment.
If you must lay the cables to run parallel, pass the power cable and the signal cable through a metal
conduit. Additionally, ground the conduit.
 If using stranded cable, ensure strands from one core do not make contact with the other core
strands.
 Use a flathead screwdriver (3.5 mm wide or less, 0.5 mm thick or less) to perform wiring.

4-6-1 Recommended cables<4 - 20 mA models>Communication
methodRecommended cables

Power source

CVV or other two-core cable (1.25 mm2)

4 - 20 mA

CVVS or other shielded cable (1.25 mm2)

Contacts

CVV or similar cable (1.25 mm2)

<ET models>Communication
methodPoE+

Recommended cables
Ethernet cable (category 5e or better)<EA models>Communication
methodRecommended cables

PoE+

Ethernet cable (category 5e or better)

Power source

CVV or other two-core cable (1.25 mm2)

4 - 20 mA

CVVS or other shielded cable (1.25 mm2)

Contacts

CVV or similar cable (1.25 mm2)

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4. Installation

4-6 Wiring procedure

4-6-2 Terminal plate specifications

4-20mA

EA<Terminal plate>
1

2

3

＋

-

＋

24 V DC

11

12

A1
ALM1

13

4

5

A1
4 - 20 mA

＋

14

15

A1
ALM2

16

A2
ALM1

6

7

A2
4 - 20 mA

＋

17

19

18

A2
ALM2

8

9

B1
4 - 20 mA

＋

20

B1
ALM1

10

B2
4 - 20 mA

21

22

B1
ALM2

23

24

B2
ALM1

25

26

B2
ALM2

27

28

FAULT

NOTE
 With EA models, do not use 24 V DC terminals 1 and 2 when using the PoE+ connection.

<Terminal plate specifications> Rated voltage: 300 V AC
 Rated current: 10 A
However, this will vary depending on the cable used.

<Connecting conditions> Solid wire cable, flexible stranded wire: 0.08 - 2.5 mm2
 Flexible stranded wire fitted with ferrule: 0.25 - 2.5 mm2
 Insulation stripped length: 8 - 9 mm
 Tools for connection: Flathead screwdriver (3.5 mm wide or less, 0.5 mm thick or less) (Manufacturer
tool: 210-720)

CAUTIONBe sure to strip the cable to the specified length.
 Conduction faults or overheating may result if the stripped wire length is too short and the wire isclamped incorrectly.
 Conduction faults or overheating may result if the stripped wire length is too short and the wire
sheathing is clamped.
 An insulation failure or short circuit may result if the stripped wire length is too long and the wire is
exposed.
 Make sure the wire does not splay. Insulation failure or overheating may result if the wire splays wheninserted.
8 - 9 mm

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4. Installation

4-6 Wiring procedure<Compatible bar terminals>
Use the following bar terminals:
 Bar terminal (ferrule): Model 216 series (WAGO)
 Crimping tool: Variocrimp 4 (206- 204) (WAGO)

CAUTION Be sure to use the specified bar terminal. Performance is guaranteed only for the bar terminals
specified.

4-6-3 Terminal plate connections
Use a flathead screwdriver (3.5 mm wide or less, 0.5 mm thick or less) to connect the cables to theterminal plate.

CAUTION Be sure to use the correct tools.
 In general, connect only one cable to one wire inlet.

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4. Installation

4-6 Wiring procedure

4-6-4 Grounding terminal connections
WARNING Be sure to ground the product before supplying power.
 Ground the product to ensure stable operation and safety. Never connect grounding wires to gas pipes.
 Make sure the grounding is Class D or equivalent (grounding resistance not exceeding 100 Ω).
 Use cable lugs on the grounding wire to ensure safe grounding with the cable free of slack and twisting.
 Do not ground to or near the same point used to ground other high-frequency devices or high-voltage
devices.

<Connection example: 4 - 20 mA models>
GD-84D-EX-EC
GD-84D-EX

Stabilized
power supply(24 V DC)

Upstream(DCS, PLC)

<Connection example: ET models>
GD-84D-EX-ET-EC
GD-84D-EX-ET

Upstream(PC, PLC)

Switching hub(With PoE+
functionality)

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4. Installation

4-6 Wiring procedure<Connection example: EA models (24 V DC)>
GD-84D-EX-EA-EC
GD-84D-EX-EA

Upstream(PC, PLC)

Switching hub
Stabilized
power supply(24 V DC)

Upstream(DCS, PLC)

<Connection example: EA models (PoE+)>
Upstream(PC, PLC)

GD-84D-EX-EA-EC
GD-84D-EX-EA

Switching hub(With PoE+
functionality)

Upstream(DCS, PLC)

* Avoid using 24 V DC power supply and PoE+ at the same time.

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4. Installation

4-7 Pipe installation

4-7 Pipe installation
Install the pipes for the sampling pipes (GAS IN, GAS OUT) as shown in the following diagram:
The supported piping is Teflon pipe of φ6 (OD) to φ4 (ID).

Union

FerruleSleevePipe

NOTE
 The sampling pipe openings (GAS IN, GAS OUT) for the unit feature Rc1/4 screw holes. On thestandard product these are fitted with polypropylene unions. The material may differ depending on
the gases used. State specific materials for the unions, if necessary.
 To prevent leaks, fit the supplied ferrules and sleeves when laying pipes.
 When pipes are cut, the cut surface may be narrower than the specified inner diameter. In this case,use a file or other implement to widen the inner diameter. Clean the pipe interior using compressed
air or the like to blow off any remaining swarf before connecting to the product.
 Note that the sample gas may be highly absorptive or corrosive. Keep this point in mind whenselecting piping materials.
 Within the specified range of operating temperatures, the suction flow rate for this product by itself
is approximately 0.6 L/min. Please consult with us for more information on factors such as pipe
length when samples are to be drawn from distant points.

WARNING Do not apply excessive pressure to the product’s sampling pipe openings.
This product is designed to perform gas detection by drawing in gas at atmospheric pressure.
Applying excessive pressure to the product’s sampling pipe openings (GAS IN, GAS OUT) ishazardous. Doing so may cause the detection target gas to leak from the product.
 Discharge the gas exhausted after detection to a location determined to be safe by connecting an
exhaust pipe to the detection target gas outlet (GAS OUT) located on the bottom of the main unit.

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4. Installation

4-7 Pipe installation

CAUTION Make the piping on the GAS IN side as short as possible.
The longer the piping on the GAS IN side, the more time it will take for the gas to arrive. Additionally,
depending on the gas, the effects of absorption may increase, causing delays in response or
readings showing reduced values.
 Make sure no condensation occurs while installing the pipes.
High humidity in the sampling source area may result in condensation within the piping. For gasesthat become more corrosive when dissolved in water (e.g., highly acidic gases), consequences may
include impaired capacity to detect gases and corrosive damage to internal parts.
 Do not lay piping that includes U or V shaped angles. Keep this in mind when performing the
installation work.
 Choose the position of the sampling inlet for the sampling gas after carefully considering gas flow
inside the sampling gas line, gas generation process, and other factors.
 Be sure to fit the supplied dust filter at some point in the piping.
 Please contact our sales department for more information on piping length and materials.

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5. Usage Instructions

5-1 Preparations for startup

5

Usage Instructions
5-1 Preparations for startup
Perform the following checks before connecting the power supply.
Failure to perform these checks may result in electric shock or damage to the product.
 Check to confirm the product is grounded.
 Check to confirm that the external wiring is connected correctly.
 Check to confirm that the power supply voltage is within the rated range.
 External contacts may activate while adjustment is underway.
Take precautions to prevent unwanted consequences due to activated contacts.
 Check to confirm that the connected piping is free of blockages and leaks.
Blockages in connected pipes will generate excessive pressure on the sensors, which can lead tomalfunctions or failure. Depending on the sensor, blockages may also cause fluctuations in readings
and false alarms.
 If a filter is required, confirm that the correct filter is fitted properly. Make sure the filter is suitable for thedetection target gas.

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5. Usage Instructions

5-2 Turning on the power

5-2 Turning on the power
To start the product, turn on the power switch on the underside of the main unit.
Before turning on the power switch, confirm that the product is properly connected to an appropriate
power source.
Power switch

Initialization will take place after the power is turned on. This will take approximately 25 seconds. The
process performs system checks and disables alarms, and performs other startup settings, then enters
detection mode.
After the power is turned on, the LCD display changes automatically as shown below:
Fully illuminated display

Initialization

Gas specification display

Detection mode

WARNING For oxygen deficiency models, the gas specification display will indicate a value around [20.9](vol%) when started in air. For models with alarms triggered by air output (0 - 5 vol%, etc.), an alarm
may occur after starting. Be careful regarding this point.

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5. Usage Instructions

5-2 Turning on the power

CAUTION Never turn the power off during initialization. The sensor memory is read during initialization.
 Depending on the sensor type, warmup may be required before startup or after replacing thesensor. Perform warmup for the required duration. (Refer to ‘11-2 Sensor specifications’.) Alarm behavior and output signals will be unstable during warmup. To avoid problems, notify any
departments that may be affected beforehand.
 After the warmup is complete, verify that the flow display reading is the flow stipulated, thencalibrate.
 Depending on the conditions and how long the device was off, the reading may oscillate when the
power is turned on. The reading should quickly stabilize at zero.

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5. Usage Instructions

5-3 Basic operation flow

5-3 Basic operation flow
After power is turned on, pressing the keys on the product will have the following effects:
The product normally operates in detection mode
<Detection mode>

After recovery,
turn on the power to restart
MODE key(long press)<User mode><First alarm>

MODE key(long press)<Second alarm><Maintenance mode><Fault alarm><Alarm test>

TEST/SET key(long press)

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5. Usage Instructions

5-3 Basic operation flow

WARNING When in an alarm state in detection mode, switching to user mode or maintenance mode will reset
the alarm.

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5. Usage Instructions

5-4 User mode

5-4 User mode
Switch to user mode to perform zero calibration and to check various settings.

5-4-1 User mode setting items
LCD display

Setting item

Details

1- 1 AIRAir calibration

Perform air calibration.

1- 2 CONFIRM

Setting display

Displays the current values for the following
settings:
・ First alarm setpoint (ALM1)・ Second alarm setpoint (ALM2)
・ Alarm delay time・ Zero suppression value
・ Zero following settings
・ Sensitivity correction settings

1- 3 FLOW

Total flow display

Displays the current flow.

1- 4 ADDRESS

Not used1- 5 84D VER

Version display for main unit andterminal unit

Displays the version of the main unit andterminal unit.

1- 6 SEN VER

Version display for sensors

Displays the versions of sensor programs.

1- 7 NET VER

Version display forcommunication PCB

Displays the version of communication PCB
programs.

1- 8 M MODE

To maintenance mode

Switches to maintenance mode.

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5. Usage Instructions

5-4 User mode

5-4-2 Switching to user mode1

In detection mode, hold down the MODE key (about
three seconds).

Switches to user mode.
After making the settings, hold down the MODE
key for about three seconds in user mode to switch
to detection mode.

WARNING Once the operations are complete, hold down the MODE key to return to detection mode.
The product will not detect gases while in the adjustment/setting state. If left in user mode, theproduct will return to detection mode after 10 hours. Note that this is dangerous because nomonitoring occurs during this time.

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5. Usage Instructions

5-5 Performing air calibration (AIR)5-5 Performing air calibration (AIR)
Perform air calibration. This is required to ensure accurate measurement of gas concentrations.
To perform air calibration, connect an air calibration gas to the product.
Refer to ‘7-5-3 Connecting the calibration gas’ for more information.

CAUTION Wait for the reading to stabilize after starting this product and before performing air calibration.

NOTE
 On oxygen deficiency models, [1- 1 AIR] will be span adjustment. Introduce clean air to adjust to[20.9] (vol%). Refer to ‘7-5-2 Running span adjustment’ for more information.

1

In user mode, press the ▲ key or ▼ key to select[1- 1 AIR], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select the sensor to
be air calibrated.
Press the ▲ key or ▼ key to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2]⇔Select all.
[----] for the selected sensor blinks.

3

Connect the calibration gas to this product.
Connect the gas sampling bag for air calibration andthe gas sampling bag for exhaust gas to the product.
(Refer to ‘7-5-3 Connecting the calibration gas’.)Before performing air calibration for each sensor,
switch the flow passage in the chamber switching unit
to match the selected sensor.

4

When all are selected

When [A1] is selected

When all are selected

When [A1] is selected

Press the TEST/SET key to confirm the sensor to
be calibrated.
This step confirms that the selected sensor and theflow passage match.

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5. Usage Instructions

56

5-5 Performing air calibration (AIR)Introduce the air calibration gas. Press the
TEST/SET key when the readings stabilize.
Air calibration starts.

When all are selected

When [A1] is selected

When all are selected

When [A1] is selected

Check the air calibration results.
If air calibration is successful[OK] is displayed. The display returns to thedisplay in step 2.
If air calibration failed[NG] is displayed. The display returns to thedisplay in step 2.

7

Disconnect the calibration gas from this product.
When air calibration is complete, disconnect the gas sampling bag for air calibration and the gas
sampling bag for the exhaust gas. (Refer to ‘7-5-4 Disconnecting the calibration gas'.)After performing air calibration for each sensor, return the chamber switching unit to the [D] (detectionmode) position.

8

Press the MODE key.
The display reverts to the [1- 1 AIR] display.

9

Hold down the MODE key for about three seconds to switch to detection mode.

NOTE The information displayed in the maintenance display section during air calibration will depend on
the sensor selected.

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5. Usage Instructions

5-6 Checking setting values (user mode)

5-6 Checking setting values (user mode)
5-6-1 Checking the alarm setpoints (CONFIRM)
Display the first alarm setpoint, second alarm setpoint, alarm delay time, zero suppression value, zero
following setting, and sensitivity correction settings.

NOTE
 The zero follower function ON/OFF display is displayed only for new ceramic sensors or for sensors
based on the electrochemical detection principle.
 The sensitivity correction function ON/OFF display is displayed only for sensors based on theelectrochemical detection principle.

1

In user mode, press the ▲ key or ▼ key to select[1- 2 CONFIRM], then press the TEST/SET key.

2

Check the different setting values.
Press the ▲ key or ▼ key to view different settings.
・ First alarm setpoint display
Displays the first alarm setpoint.

・ Second alarm setpoint display
Displays the second alarm setpoint.

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5. Usage Instructions

5-6 Checking setting values (user mode)・ Alarm delay time display
Displays the alarm delay time (in seconds).

・ Zero suppression value display
Displays the zero suppression value.

・ Zero follower ON/OFF display
Displays the zero follower ON/OFF setting.
(Refer to ‘6-4-2 Zero follower function’.)・ Sensitivity correction ON/OFF display
Displays the sensitivity correction ON/OFF setting.
(Refer to '6-4-3 Sensitivity correction function’.)Press the ▲ key to return to the first alarm setpoint display.

3

Press the MODE key.
The display reverts to the [1- 2 CONFIRM] display.

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First alarm setpoint display

5. Usage Instructions

5-6 Checking setting values (user mode)

NOTE The first alarm setpoint, second alarm setpoint, and alarm delay time can be set in Environmental
setting 1 in maintenance mode. (Refer to ‘7-9 Making changes in Environmental setting 1’.)
 The zero suppression value, zero follower ON/OFF setting, and sensitivity correction ON/OFF
setting can be set in Environmental setting 2 in maintenance mode. (Refer to ‘7-10 Making changes
in Environmental setting 2’.)

5-6-2 Checking flow values (FLOW)
Display the current flow value (L/min).
1

Press the ▲ key or ▼ key in user mode to select[1- 3 FLOW], then press the TEST/SET key.

2

Check the current flow value (L/min).
Displays the total value for flow passage A and flow passage B.

3

Press the MODE key.
The display reverts to the [1- 3 FLOW] display.

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5. Usage Instructions

5-6 Checking setting values (user mode)

5-6-3 Checking the version of the main unit (84D VER)
Display the ROM/SUM value for the main unit and the ROM/SUM value for the terminal unit.
The ROM/SUM value for the terminal unit is displayed only for 4 - 20 mA and EA models.
1

Press the ▲ key or ▼ key in user mode to select[1- 5 84D VER], then press the TEST/SET key.

2

Check the ROM/SUM values.
Press the ▲ key or ▼ key to switch between viewing the
ROM/SUM value for the main unit and the ROM/SUM
value for the terminal unit.
・ Display showing ROM/SUM value for main unit

・ Display showing ROM/SUM value for terminal unit

3

Press the MODE key.
The display reverts to the [1- 5 84D VER] display.

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5. Usage Instructions

5-6 Checking setting values (user mode)

5-6-4 Checking the sensor versions (SEN VER)
Displays ROM/SUM values for the sensors currently fitted.
1

Press the ▲ key or ▼ key in user mode to select[1- 6 SEN VER], then press the TEST/SET key.

2

Check the sensor ROM/SUM values.

3

Press the MODE key.
The display reverts to the [1- 6 SEN VER] display.

5-6-5 Checking the communication PCB version (NET VER)
Display the ROM/SUM value for the communication PCB currently connected.
1

Press the ▲ key or ▼ key in user mode to select[1- 7 NET VER], then press the TEST/SET key.

2

Check the communication PCB ROM/SUM value.

3

Press the MODE key.
The display reverts to the [1- 7 NET VER] display.

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ET

EA

5. Usage Instructions

5-7 Shutting down

5-7 Shutting down
To turn off the product, turn the power switch on the underside of the main unit OFF in detection mode.
Power switch

WARNING Shutting down the product may activate an alarm in the upstream (central) system.
 Shut down the product only after setting enabling INHIBIT in the upstream (central) system.
Additionally, check the devices connected to the external output of this product and the external
contact output terminals to determine whether you should turn off the power to those devices.
 If the alarm contacts are energized (optional), the contacts may respond/activate when the power
for this product is turned off.
 If the detection target gas is highly adsorbent, allow plenty of fresh air to flow before turning thepower off.

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6. Alarm Activation

6-1 Gas (oxygen) alarm pattern

6

Alarm Activation
6-1 Gas (oxygen) alarm pattern
6-1-1 Alarm Activation
The product issues an alarm when the detected gas or oxygen concentration reaches or exceeds thealarm setpoint. (Auto reset or self-latching)

NOTE The alarm setpoints (first and second alarms) and alarm pattern (auto reset or self-latching) are set
at the factory before shipping.
 An alarm delay (default setting: two seconds) is set to prevent accidental alarm activation. Thisshould be canceled if not required. (Refer to ‘7-9-3 Alarm delay time setting (ALM DLY)’.)<Gas concentration display>
The display at the sensor mounting position where the alarm is occurring blinks. (The first alarm flashes once
every 2 seconds, the second alarm flashes once every 1 second)

If the detection range is exceeded (full scale over), [OVER] will appear on the LCD.

<Power/alarm lamp display>
The alarms are two-step alarms. The alarm lamps light up when the corresponding alarm setpoint isreached or exceeded.
Alarm lamp (ALM1) and alarm lamp (ALM2) light up (red) as indicated below.
The power lamp (POWER) continues to light up (green).
<First alarm><Second alarm>

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6. Alarm Activation

6-1 Gas (oxygen) alarm pattern

6-1-2 Contact operation (auto reset)

4-20mAEA

If the Gas alarm pattern setting is auto reset, the contacts will activate when the gas concentration
reaches or exceeds the alarm setpoint.
The contact operation is automatically reset when the gas concentration falls below the alarm setpoint.

NOTE To cancel an alarm, press the MODE key, TEST/SET key, ▲ key, or ▼ key in detection mode.

<Alarm pattern (H-HH)>
Normal

Alarm

Reset

Gas concentration■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact<Alarm pattern (L-H)>
Normal

Alarm

Reset

Alarm

Reset

Gas concentration■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact<Alarm pattern (L-LL)>(Oxygen deficiency alarm)
NormalAlarm

Gas concentration■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact

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Reset6. Alarm Activation

6-1 Gas (oxygen) alarm pattern

6-1-3 Contact operation (self-latching)

4-20mAEA

If the Gas alarm pattern setting is self-latching, the contacts will activate when the gas concentration
reaches or exceeds the alarm setpoint.
The contact operation is automatically reset when the gas concentration falls below the alarm setpoint
after resetting.
The alarm lamps flash when an alarm occurs. The lamps stop flashing and remains constantly lit whenreset. Then, the lamps go out when the gas concentration falls below the alarm setpoint.

<Alarm pattern (H-HH)>
Normal

Alarm

Reset

Gas concentration

Reset

Reset

■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact

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6. Alarm Activation

6-1 Gas (oxygen) alarm pattern<Alarm pattern (L-H)>
Normal

Alarm

Reset

Alarm

Reset

Gas concentration

Reset

Reset

■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset

Reset

■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact

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6. Alarm Activation

6-1 Gas (oxygen) alarm pattern<Alarm pattern (L-LL)>(Oxygen deficiency alarm)
Normal

Alarm

Reset

Gas concentration

Reset

Reset

■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact
Reset■ ALM1 alarm lamp (red)■ ALM2 alarm lamp (red)■ ALM1 alarm contact■ ALM2 alarm contact

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6. Alarm Activation

6-1 Gas (oxygen) alarm pattern

6-1-4 Response when a gas alarm is triggered
When a gas alarm is triggered, respond promptly in accordance with the user's management rules.
In general, take the following actions:
Step 1 Check the product reading.

CAUTION In the case of momentary gas leaks, readings may already have dropped by the time the reading ischecked. Additionally, readings may drop in the temporary alarm state for reasons other than gas
alarms, such as noise and incidental conditions.

Step 2 Keep persons out of the monitored zone to ensure safety in accordance with your gas
alarm control concentrations.
Step 3 If the gas concentration display remains unchanged, close the main valve for the gas inquestion and confirm that the concentration reading has dropped.
Step 4 Wear appropriate protective gear to safeguard against hazards involving residual gas andaccess the gas leakage location. Use a portable gas detector to check for residual gas.
Step 5 Once you have determined that no hazards are present, take the steps necessary to fix thegas leak.

CAUTION A full scale over state for extended periods may indicate sensor damage. Contact with high gas
concentrations will damage the sensor. Contact our sales department.
 Depending on the type of gas detected, the sensor characteristics may be severely degraded. If thegas alarm is triggered, we recommend performing maintenance on all sensors fitted to this productto check their gas sensitivity.

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6. Alarm Activation

6-2 Fault alarm patterns

6-2 Fault alarm patterns
Fault alarms are triggered if abnormalities are detected in the product or sensors.
When a fault alarm is triggered, the fault lamp (FAULT) lights up (yellow). The fault code will appear on the
LCD.

<LCD display>
When a sensor fault occurs, a fault code is displayed for each sensor.
If a main unit fault and sensor fault are detected at the same time, the main unit fault and sensor fault are
displayed alternately.
<Main unit fault>(With a flow loss fault [E-51 FLOW])<Sensor fault>(With a set potential fault [E-13])<Power/fault lamp indications>

FAULT lights up (yellow)

NOTE Following fault recovery, initialization is performed and it restarts.
 Refer to ‘10. Troubleshooting’ for more information on faults and appropriate response.
 If a fault alarm occurs, determine the cause and take appropriate action.
 If faults occur repeatedly, contact Riken Keiki immediately.
 The system enables fault alarm tests. (Refer to ‘7-9-4 Fault alarm tests (F TEST)’.)

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6. Alarm Activation

6-3 External output operations

6-3 External output operations
Communication
method

4 - 20 mA

Ethernet

Signal transmission
methodAnalog transmission (non-insulated)

Ethernet (10BASE-T/100BASE-TX)

Transmission path

CVVS

Ethernet cable

Transmission
distance

1 km or less

100 m or less (depending on system
conditions)

Connected load
resistance300 Ω or less-1

<Normal>
4 - 20 mA (Concentration output)

・ Concentration data

Detectionmode(No alarm)<With dummy sensor connected>
2.5 mA setting: 2.5 mA
4 mA, HOLD, 4 - 20 mA setting: 4 mA
(depending on maintenance mode setting)2

Detection
mode(During a gas
alarm)<Normal>
4 - 20 mA (Concentration output)

・ Concentration data
・ Bit settings for various alarms

3

Initialization

2.5 mA setting: 2.5 mA
4 mA, HOLD, 4 - 20 mA setting: 4 mA*(depending on maintenance mode setting)・ Initialization bit

4

Maintenancemode

2.5 mA setting: 2.5 mA
4.0 mA setting: 4.0 mA*
HOLD setting: Maintain previous value
4 - 20 mA setting: 4 - 20 mA (Concentration
output)・ Concentration data・ Adjustment bit

5

Alarm test

Output ON setting: 4 - 20 mA(Concentration output)
Output OFF setting: Maintain previous
value・ Concentration data・ Adjustment bit・ Test bit

6

Fault alarms

0.5 mA setting: 0.5 mA
21.5 mA setting: 21.5 mA
Option setting: Setting possible 0.0 - 4.0 mA・ Bit settings for various faults

7

INHIBIT

2.5 mA setting: 2.5 mA
4 mA, HOLD, 4 - 20 mA setting: 4 mA*(depending on maintenance mode setting)・ Concentration data・ Adjustment bit
・ INHIBIT

8

Power off

0 mA

・ Signal OFF<With dummy sensor connected>
2.5 mA setting: 2.5 mA
4 mA, HOLD, 4 - 20 mA setting: 4 mA
(depending on maintenance mode setting)* Equivalent to air (20.9 vol% = 17.4 mA) when F.S. 25.0 vol% O2 is measured
Equivalent to air (21.0 vol% = 10.7 mA) when F.S. 50.0 vol% O2 is measured(Alarm types: L-LL and L-H only)

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6. Alarm Activation

6-3 External output operations<Analog transmission (4 - 20 mA)>
<Example of gas concentration and external output>
Maintenance output : 2.5 mA setting
Fault output: 0.5 mA setting
External output
22 mA
20 mA

Detection mode
Maintenance mode

4 mA
2.5 mAGas concentration0

Full scale

Zero suppression

NOTE If the fault output is 21.5 mA, the upper limit will be 20.5 mA. In the option setting, the upper limit is
22 mA as is the case of 2.5 mA.

CAUTION
 4 - 20 mA output setting has already been adjusted. Output will not exceed approximately 22 mA if
an over scale occurs.
 If the INHIBIT function is enabled/active or during initialization, the output will be based on the 4 - 20
mA output setting (as in maintenance mode).
Be particularly careful while the product is starting and when changing the specifications.
 Make sure you have a good understanding of this behavior. If necessary, take the necessary steps
on the receiver (e.g., put into skip state.) so that no false alarms occur.
 Outputs dependent on sensor settings will be updated after replacement of the sensor.
The following cases in particular require special care:
・ Replacement when [C-02] is displayed: When replacing a sensor whose detection target
gas is O2 with a sensor for a gas other than O2
・ Replacement when [C-02] is displayed: When replacing a sensor whose detection target
gas is other than O2 with a sensor for O2
・ Replacement when changing the alarm type : Replacing L-LL type and L-H type sensors with HHH type sensors

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6. Alarm Activation

6-3 External output operations<GD-84D-EX-ET communication specifications (Ethernet)>
The following functions are provided through connections to external software using standard network
protocols. Refer to the ‘Gas Detector Head GD-84D-EX Series (Ethernet model) Communication
Functions Operating Manual’ for more information.
 Web function(s) (HTTP)
Use a web browser from a connected PC to view and change settings, execute calibration, and perform
tests through the graphical user interface.
 Mail transmission function (SMTP)
Notifications are sent to the addresses registered on an external mail server if gas alarms or fault
alarms are triggered.
 Time synchronization function (SNTP)
Time data is acquired from a time server to keep the time up to date.
 Modbus slave function (Modbus/TCP)
The product can function as a Modbus slave, returning settings with responses to read requests andmodifying settings with write requests.
 Function for connecting to PLCs (FINS/MC)The settings are sent to the PLCs and data provided so the PLCs can process with a ladder program.
Loading from PLCs is also performed to enable modification of settings as well as calibrations and tests.

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6. Alarm Activation

6-4 Various functions to ensure proper alarm activation

6-4 Various functions to ensure proper alarm activation
6-4-1 Zero suppression function
The sensors incorporated into the product are susceptible to fluctuations in ambient conditions (e.g.,temperature and humidity characteristics) and interference gases (interference characteristics). These canaffect readings. This means readings may fluctuate around zero levels even under normal conditions.
The zero suppression function is designed to minimize the effects of these ambient fluctuations andinterference gases around the zero level. Use this function to suppress fluctuations in readings of lessthan the preset value to give zero readings (or [20.9] (vol%) for oxygen).
For example, HF readings will be indicated as follows:<Zero suppression function disabled><Zero suppression function enabled>

The reading fluctuates around zero.

Displays zero up to the standard setting value(6 % F.S. (0.09 ppm))

NOTE
 The standard preset value for the zero suppression function differs depending on sensor
specifications.
 This function is disabled in maintenance mode. Fluctuations in readings of less than the value set
are displayed.
 When an oxygen deficiency alarm model sensor (ESF-X24P: 0 - 25 vol%) is fitted, the zero
suppression function works on the atmosphere (20.9 vol%), which is the normal value. In this case,if readings fluctuate near 20.9 vol%, the reading displayed is [20.9] (vol%) (AIR suppression).

CAUTION The negative suppression value (below zero) is subject to suppression corresponding to 10 % of fullscale. If the value below zero becomes 10 % of full-scale or larger, the reading will be displayed as[-0.0], and accurate gas detection will not be possible in this state. Perform zero calibration.

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6. Alarm Activation

6-4 Various functions to ensure proper alarm activation

6-4-2 Zero follower function
Depending on sensor specifications, the sensors used in the product may suffer sensitivity degradation
when used for extended periods.
The zero follower function is programmed processing designed to stabilize the zero point by correcting
fluctuations in readings (zero drift) caused by the sensitivity variation over time of the zero point.

NOTE The zero follower function is available for the new ceramic sensors and sensors based on theelectrochemical detection principle.
 The 24-hour zero follower function performs zero following only for the first 24 hours after the poweris turned on.
<Zero follower function OFF>

<Zero follower function ON>
Reading

Reading

Zero
point

0

Zero
point

0

Time

Time

Sensor zero drift appears in readings.

Zeroing is performed periodically.

6-4-3 Sensitivity correction function
Depending on type, the electrochemical type sensor used in the product may suffer sensitivity degradation
when used for extended periods. The sensitivity correction function is designed to compensate for (assist)gas sensitivity degradation accounting for variations in sensitivity over time. Span adjustment is performed
according to programmed processing based on theoretically derived degradation trends.

NOTE

 The sensitivity correction function is available for sensors based on the electrochemical typedetection principle.
<Sensitivity correction function OFF>

<Sensitivity correction function ON>

Reading

Reading

Calibration0

Sensor sensitivity degrades.

Calibration

0

Time

Time

Span adjustment is performed periodically.

CAUTION The sensitivity correction function is a support function. Fixed span adjustment is performed basedon theoretically derived degradation trends. Span adjustment is not performed based on theindividual sensitivity variations of each sensor.
 Corrections of individual sensors’ sensitivity variations must be performed as periodic span
adjustment using a calibration gas.

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6. Alarm Activation

6-4 Various functions to ensure proper alarm activation

6-4-4 Calibration history, alarm trend history, and event history functions
History functions are available for both the device and for the sensors.
Contact our sales department if you want to use the calibration history, alarm trend history, or event history
functions.

6-4-5 Automatic sensor recognition function
This product features a function that automatically recognizes the sensor after a sensor is replaced or if
specifications change.
The following display warns against incorrect mounting if a sensor with a different serial number, detection
principle, or specifications is mounted:<When replaced with a sensor based on the same specifications>
The display indicates [C-01] if the sensor is replaced with a sensor of the same specifications (e.g.,
detection principle and model)—for example, upon periodic replacement.
Press the TEST/SET key to recognize the sensor as a new sensor and to start up.

<When replaced with a sensor based on different specifications>
The display indicates [C-02] if the sensor is replaced with a sensor of different specifications (e.g.,
detection principle and model).
Press the TEST/SET key to recognize the sensor as a sensor with new specifications and to start up.
If you did not intend to change the specifications, the sensor may have been mounted by mistake. Checkthe sensor.

<If replacement couldn't be completed correctly>
If there is a problem with the sensor combination or if a sensor cannot be used, [C-03] or [C-04] willappear. The product will not return to detection mode.
Confirm the sensor combination (sequence) and contact our sales department.

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6. Alarm Activation

6-4 Various functions to ensure proper alarm activation

CAUTION
 Confirming changes in sensor specifications (e.g., detection principal, sensor type, detection target
gas, and detection range) when [C-02] is displayed will reflect the changes in gas detector
specifications.
The following parameters (including alarm setpoints) will be reset to their initial values.
Change the parameters in maintenance mode if values other than the initial values are required.
・ Alarm delay time・ Zero suppression value
・ Alarm type
<Initial settings for each type of detection principle>
NCF
SGF
SHF
ESF
Alarm delay time
2 seconds
2 seconds
2 seconds
2 seconds
F.S. 100 % LEL: 2 % F.S.
Zero suppression
10 % F.S.
10 % F.S.
6 % F.S.
value
Other: 10 % F.S.
Alarm type
H-HH
H-HH
H-HH
H-HH
 In maintenance mode, settings for external output remain unchanged from before the sensor
replacement. Take particular note of this.
 When [C-02] appears, confirming with TEST/SET will start initialization at the same time theoperation switches over. The initialization output also switches in conjunction.
 The oxygen deficiency alarm ESF models include three types of alarms: L-LL, L-H, and H-HH.
The order of the alarm reverses when you change from L-LL or change to L-LL.
 For ET and EA models, before confirming changes in sensor specifications, the data from thesensor with different specifications will be output.

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7. Maintenance

7-1 Maintenance intervals and maintenance items

7

Maintenance
The product is an important safety and disaster-prevention device.
Perform product maintenance at regular intervals to ensure performance and to improve disasterprevention and safety reliability.

7-1 Maintenance intervals and maintenance items
Perform the following maintenance.
 Daily maintenance:
Perform maintenance before commencing work.
 Monthly maintenance: Inspect the alarm circuit (alarm test) once a month.
 Regular maintenance: Perform maintenance at least once every six months to ensure adequate
performance as a safety device.
Maintenance
item

Maintenance details

Power supply
check

Check to confirm that the power LED lights up.

Concentration
display check

Daily
Monthly
Regularmaintenance maintenance maintenance

○

○

○

Confirm that the concentration readout is zero ([20.9](vol%) for oxygen). If the reading is offset, confirm
that there is no interference gas in the vicinity andperform zero calibration (air calibration).

○

○

○

Flow check

Check the flow display and confirm the absence of
any abnormalities.

○

○

○

Filter check

Check to confirm that the dust filters are not dirty or
clogged.

○○○

Alarm test

Use the alarm test function to check the alarm circuit.

○○

Calibration

Perform calibration using a calibration gas.

Gas alarm
check

Check the gas alarm using a calibration gas.

○○

<Maintenance service>
Riken Keiki provides services related to regular maintenance, including gas calibration, adjustments, andservicing.
Preparing a calibration gas requires dedicated equipment, including gas cylinders of the specified
concentration and gas sampling bags. Our certified service engineers have expert knowledge of these
dedicated tools and products.
Please take advantage of the Riken Keiki maintenance service to maintain safe use of the product.

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7. Maintenance

7-1 Maintenance intervals and maintenance items

The major maintenance items are as follows. Contact our sales department for more information.
Service

Service details

Power supply check・ Check voltage of power source.
・ Check to confirm that the power LED lights up.
(Confirm that you can distinguish between the system power lamp
(POWER), alarm lamps (ALM1, ALM2), and fault lamp (FAULT).)・ If a UPS (uninterruptible power system) is deployed, confirm operations with
the UPS.

Concentration display
check

Using zero gas, confirm that the concentration reading is zero. Perform zero
calibration (air calibration) if the reading is offset.
For oxygen deficiency alarm models, introduce clean air and confirm that theconcentration reading becomes [20.9] (vol%). Perform span adjustment if thereading is offset.

Flow check

Confirm the absence of abnormalities in the flow display.
Use an external flowmeter to check the flow. Check to confirm that the flow
display of this product is correct. Make flow adjustments if the flow is offset.

Filter check

Check to confirm the dust filters are neither dirty nor clogged.
Replace the filter if clearly dirty or clogged.

Alarm test

Perform the alarm test function to inspect the alarm circuits.
・ Check the alarm lamps (check operations for both ALM1 and ALM2)・ Check external alarms (check buzzer and other external alarm operations)

Calibration

Perform gas calibration with a calibration gas.

Gas alarm check

Check the gas alarm using a calibration gas.
・ Check alarms (confirm alarm activation when alarm setpoint is reached)・ Check delay time (check delay time until alarm activation)
・ Check the alarm lamps (check operations for both ALM1 and ALM2)・ Check external alarms (check buzzer, reset signal, or other external alarm
operations)

Product cleaning andrepair(visual inspection)

Check the product exterior, covers, and interior for dirt and damage, andclean and repair problem areas.
Replace parts if cracked or damaged.

Product operation check

Operate the keys to check the behavior of various functions and theparameters.

Consumable parts
replacement

Replace degraded components such as sensors, filters, and pumps.

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7. Maintenance

7-2 Performing alarm tests

7-2 Performing alarm tests
A signal is emitted that simulates a gas concentration, enabling checks of the alarm lamps and the statusof signal transmissions to external devices.

WARNING Before starting an alarm test, notify the related departments so that measures can be taken to
ensure that problems do not arise due to external output signals or alarm contacts.
 When the alarm test is complete, hold down the TEST/SET key to return to the detection mode. The
product will not detect gases while in the adjustment/setting state. If left in alarm test mode, theproduct will return to detection mode after 10 hours. Note that this is dangerous because nomonitoring occurs during this time.

1

In detection mode, hold down the TEST/SET key for about 3
seconds.
Switches to alarm test mode.

2

Press the ▲ key or ▼ key to select the sensor for which
the alarm test is to be performed.
Press the ▲ key or ▼ key repeatedly to cycle throughthe following settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The concentration for the selected sensor blinks.

3

Press the TEST/SET key to confirm the sensor to be tested.

4

Press the ▲ key or ▼ key to set the concentration.

5

Check to confirm that an alarm is triggered.
The first alarm is triggered when the concentration reaches thefirst alarm setpoint.
When the first alarm is triggered, the alarm lamp (ALM1) lights
up (red).
When [TEST ON], then the contact of the first alarm isactivated.

Alarm lamp (ALM1)
lights up (red)79 / 191

7. Maintenance

7-2 Performing alarm tests

The second alarm is triggered when the concentration reaches
the second alarm setpoint.
When the second alarm is triggered, alarm lamp (ALM1) andalarm lamp (ALM2) light up (red).
When [TEST ON], then the contact of the second alarm isactivated.

Alarm lamps (ALM1/ALM2)
light up (red)6

Press the TEST/SET key to reset the reading.

7

Press the MODE key.
The display reverts to the display in step 2.
To continue making settings for other sensors, repeat steps 2 to 7.

8

Once the operation is complete, hold down the SET key for about 3 seconds to switch todetection mode.

NOTE
 Contacts will operate during alarm tests if [TEST ON] is displayed; they will not operate if[TEST OFF] displayed. Set whether there is contact operation during alarm tests in Environmental
setting 2 in maintenance mode. (Refer to ‘7-10-4 Settings for contacts during alarm tests (TESTRLY)’.)
 Set whether there is external output during alarm tests in Environmental setting 2 in maintenancemode. (Refer to ‘7-10-5 Settings for external output during alarm tests (TEST4-20)’.)80 / 191

7. Maintenance

7-3 Maintenance (regular maintenance) mode

7-3 Maintenance (regular maintenance) mode
Switch to maintenance mode to perform zero calibration, make span adjustments, and to make various
other settings.

7-3-1 Maintenance mode setting items
LCD display

Setting item

Details

2- 0 GAS TEST

Gas introduction test

Perform a gas introduction test.

2- 1 ZERO

Zero calibration

Perform zero calibration.

2- 2 SPAN

Span adjustment

Perform span adjustment.

2- 3 LAST CAL

Date last calibrated

Display the date on which calibration was last
performed.

2- 4 E VOLT

Set potential

Display the set potential.

2- 5 DEF FLOW

Flow value correction

Correct the flow value so that the flow becomes
0.6 L/min ± 10 % (0.54 - 0.66).

2- 6 FLOW

Flow display, flow
adjustment

Adjust the pump and display the current flow.

2- 7 TEMP

Ambient temperatures

Display the current temperature in the installation
environment.

2- 8 ----

Not used2- 9 SETTING1

Environmental setting 1

Make settings for INHIBIT, alarm setpoints, etc.
Perform fault tests and maintenance. (Refer to‘7-9 Making changes in Environmental setting 1’.)

2-10 SETTING2

Environmental setting 2

Make settings for items such as alarm patterns, fault
patterns, zero suppression values, date and time, andexternal output. (Refer to ‘7-10 Making changes inEnvironmental setting 2’.)

2-11 ----

Not used

2-12 FAULT

Not used

2-13 S SET

Sensor start setting

Set the date of first use for the sensor.

2-14 F MODE

To factory modeNot used

2-15 RETURN

To user mode

Switches to user mode.

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7. Maintenance

7-3 Maintenance (regular maintenance) mode

7-3-2 Switching to maintenance mode1

In detection mode, hold down the MODE key for about
three seconds.

Switches to user mode.

2

Press the ▲ key or ▼ key to select [1- 8 M MODE], thenpress the TEST/SET key.

3

Hold down the TEST/SET key for about three seconds.

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7. Maintenance

7-3 Maintenance (regular maintenance) mode

Switches to maintenance mode.
After making the settings, hold down the MODE key forabout three seconds in maintenance mode to switch todetection mode.

WARNING Once you are done, hold down the MODE key in maintenance mode to return to detection mode.
The product will not detect gases while in the adjustment/setting state. The product will revert todetection mode in 10 hours if left in maintenance mode. Exception: Due to the possibility that
replacement tasks are underway, the device will not revert to detection mode if left in maintenancemode while setting environmental setting 1 is underway ([2- 9 SETTING1] >[SET-3 MAINTE]). Thisis dangerous because no monitoring occurs during this time. Keep this in mind.

NOTE If password setting is ON, a password must be entered to switch to maintenance mode.
 The password is set beforehand by Riken Keiki. Please contact our sales department if you do notknow the password.
 Select [2-15 RETURN] in maintenance mode and press the TEST/SET key to switch to user mode.

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7. Maintenance

7-4 Performing a gas introduction test

7-4 Performing a gas introduction test
Perform operational checks to confirm that the sensors react to the gases.
You can check the operation of the sensors without activating the contacts, external output(s), or alarms.
The gas introduction test can be performed separately for each sensor or for all sensors at the same time.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 0 GAS TEST], then press the TEST/SET key.

2

Switch the flow passage of the product to matchthe sensor for the gas introduction test.
Before performing gas introduction tests for eachsensor, switch the flow passage in the chamberswitching unit to match the sensor. For more
information on switching the flow passage of thechamber switching unit, refer to steps 1 to 4 in ‘<Ifcalibration is to be performed for each sensor>’ in‘7-5-3 Connecting the calibration gas’.
Switching the flow passages is not necessary if thegas introduction test will be performed for all sensors.

3

Press the ▲ key or ▼ key to select the sensor forwhich the gas introduction test is to be performed.
Press the ▲ key or ▼ key repeatedly to cycle throughthe following settings: [A1]⇔[A2]⇔[B1]⇔[B2]⇔Selectall.

4

Connect the gas sampling bag for the gas
introduction test and the gas sampling bag forexhaust gas to the product, then introduce thegas.
For more information on connecting the gas sampling
bag for the gas introduction test, refer to‘7-5-3 Connecting the calibration gas’.

When all are selected

When [A1] is selected

5

Confirm that the concentration is displayed for the selected sensor.

6

Disconnect the gas for the gas introduction test from this product.
Once the gas introduction test is complete, disconnect the gas sampling bag for the gas introduction
test and the gas sampling bag for exhaust gas. (Refer to ‘7-5-4 Disconnecting the calibration gas’.)After the gas introduction test separately for each sensor, return the chamber switching unit to the [D](detection mode) position.

7

Press the MODE key.
The display reverts to the [2- 0 GAS TEST] display.

8

Hold down the MODE key for about three seconds to switch to detection mode.

NOTE When the gas introduction test is performed for each sensor, the concentration display will read[----] if the sensor and flow passage do not match. The pump will stop. If so, after switching the flow
passage of the chamber switching unit, select another sensor in the screen of step 3, then reselectthe sensor for which the gas introduction test is to be performed.

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7. Maintenance

7-5 Performing calibration

7-5 Performing calibration
Before performing calibration, prepare a gas sampling bag with the calibration gas and another gas
sampling bag for the exhaust gas.

7-5-1 Running zero calibration
Correct zero calibration is required for accurate measurements of gas concentrations.
Zero calibration is essential for accurate measurements.
Zero calibration can be performed separately for each sensor or for all sensors at the same time.

WARNING When zero calibration is performed in the atmosphere, check the atmosphere is free fromcontaminants before starting. Performing zero calibration in the presence of interference gases will
mean calibration will not be performed correctly, and is a safety hazard in the event of an actual gas
leak.

CAUTION To perform zero calibration, introduce the gas for zero calibration, then wait for the reading tostabilize.
 Perform zero calibration with the gas for zero calibration. If you introduce the wrong gas, dependingon the sensor, indication accuracy and overall response may deteriorate.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 1 ZERO], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select the sensor tobe zero calibrated.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2]⇔Select all.
[----] for the selected sensor blinks.

3

Connect the calibration gas to this product.
Connect the zero gas sampling bag and gas sampling
bag for exhaust gas to the product. (Refer to‘7-5-3 Connecting the calibration gas’.)
When performing zero calibration for each sensor, switch When all are selected
the flow passage in the chamber switching unit to theselected sensor.

4

Press the TEST/SET key to confirm the sensor to becalibrated.
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When [A1] is selected7. Maintenance

7-5 Performing calibration

This step confirms that the selected sensor and theflow passage match.

5

6

When all are selected

When [A1] is selected

When all are selected

When [A1] is selected

When all are selected

When [A1] is selected

Introduce the gas for zero calibration and press the
TEST/SET key.
Zero calibration starts.

Check the zero calibration results.
If zero calibration is successful[OK] is displayed. The display returns to the display instep 2.
If zero calibration failed[NG] is displayed. The display returns to the display instep 2.

7

Disconnect the calibration gas from this product.
When zero calibration is complete, disconnect the zero gas sampling bag and the gas sampling bag
for exhaust gas. (Refer to ‘7-5-4 Disconnecting the calibration gas’.)After performing zero calibration for each sensor, return the chamber switching unit to the [D](detection mode) position.

8

Press the MODE key.
The display reverts to the [2- 1 ZERO] display.

9

Hold down the MODE key for about three seconds to switch to detection mode.

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7. Maintenance

7-5 Performing calibration

7-5-2 Running span adjustment
Perform span adjustment. This is required to ensure accurate measurements of gas concentrations.
Perform span adjustment for each sensor.

CAUTION To perform span adjustment, introduce the gas for span adjustment, then wait for the reading tostabilize.
 Perform span adjustment using the span adjustment gas. If you introduce the wrong gas, dependingon the sensor, indication accuracy and overall response may deteriorate.
 After introducing the gas for span adjustment, supply air or gas for zero calibration and allow tostand for around five minutes.
Failure to allow enough time at this step may result in calibration problems, impaired indication
accuracy in detection mode, and slower response.

1

In maintenance mode, press the ▲ key or ▼ key to select[2- 2 SPAN], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select the sensor for whichspan adjustment is to be performed.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
[----] for the selected sensor blinks.

3

Connect the calibration gas to this product.
Connect the gas sampling bag for span adjustment and the gas
sampling bag for exhaust gas to the product. (Refer to‘7-5-3 Connecting the calibration gas’.)Switch the flow passage in the chamber switching unit to theselected sensor.

4

Press the TEST/SET key to confirm the sensor to becalibrated.
This step confirms that the selected sensor and the flow
passage match.

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7. Maintenance

7-5 Performing calibration

5

Introduce the gas for span adjustment, and press the
TEST/SET key when the concentration stabilizes.
The TEST/SET key will not work if concentrations are less than
10 % of the full scale.

6

Press the ▲ key or ▼ key to match the introduced gas
concentration.
For oxygen deficiency alarm models, adjust so that it becomes[20.9] (vol%).

7

Press the TEST/SET key.
Span adjustment starts.

8

Check the span adjustment results.
If span adjustment is successful[OK] appears.
If span adjustment failed[NG] is displayed. The display returns to the display in step 2.

9To record the results of span adjustment, press the
TEST/SET key. Press the MODE key to skip recording.

Span adjustment ends and the display returns to the display in step 2.

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7. Maintenance

7-5 Performing calibration

10 Disconnect the calibration gas from this product.
When span adjustment is complete, disconnect the span gas sampling bag and the gas sampling bag
for exhaust gas. (Refer to ‘7-5-4 Disconnecting the calibration gas’.)Return the chamber switching unit to the [D] (detection mode) position.
11 Press the MODE key.
The display reverts to the [2- 2 SPAN] display.
12 Hold down the MODE key for about three seconds to switch to detection mode.

NOTE Press the SHIFT key in step 2 to display the span adjustment margin for the selected sensor as you
hold down the key. Restart to reset the displayed margin.

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7. Maintenance

7-5 Performing calibration

7-5-3 Connecting the calibration gas
With the pump stopped, connect the gas sampling bag with calibration gas and the gas sampling bag forexhaust gas to the product.

<If calibration is to be performed for all sensors>
Connect the gas sampling bag with calibration gas to GAS IN on this product and connect the gas
sampling bag for exhaust gas to GAS OUT.

Gas
sampling
bag withcalibrationgas

Gas
sampling
bag forexhaustgas<If calibration is to be performed for each sensor>
Switch the chamber switching unit of this product to the flow passage for the sensor to be calibrated.
Connect the calibration gas.
1

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther down to open to 180°.

2

Loosen the black knurled screw in the center ofthe chamber switching unit.
Chamberswitching unit

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7. Maintenance3

7-5 Performing calibration

Pull the chamber switching unit towards you and turn to
the left or right to place the nipple in the [CAL A] or[CAL B] position.
When performing air calibration for the sensors in flow
passage A ([A1], [A2]), turn to [CAL A]. Whenperforming air calibration for the sensors in flow
passage B ([B1], [B2]), turn to [CAL B].

NippleNippleFor the sensor in flow
passage A

4

Tighten the black knurled screw while pressing
in on the chamber switching unit.

5

Connect the gas sampling bag with calibration
gas to the nipple of the chamber switching unit.

6

Connect the gas sampling bag for exhaust gas
to GAS OUT on this product.

Gas
sampling
bag withcalibrationgas

For the sensor in flow
passage B

Gas
sampling
bag forexhaustgas* The illustration shows the side for flow passage A.

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7. Maintenance

7-5 Performing calibration

7-5-4 Disconnecting the calibration gas<If calibration was performed for all sensors>
Disconnect the gas sampling bag with calibration gas and the gas sampling bag for exhaust gas from theproduct.

<If calibration was performed for each sensor>
Disconnect the gas sampling bag with calibration gas and the gas sampling bag for exhaust gas from theproduct, then return the chamber switching unit to the [D] (detection mode) position.

CAUTION Once calibration is finished, be sure to return the chamber switching unit to the [D] (detection mode)
position. Detection cannot be performed properly if the chamber switching unit is not at the [D](detection mode) position.

1

Disconnect the gas sampling bag withcalibration gas and the gas sampling bag forexhaust gas from the product.

2

Loosen the black knurled screw in the center ofthe chamber switching unit.

3

Pull the chamber switching unit towards you
and turn to the left or right to place the nipple
in the [D] (detection mode) position.

4

Tighten the black knurled screw while pressing
in on the chamber switching unit.

NippleKnurled screw

Nipple5

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

CAUTION Be sure to return the chamber switching unit to the [D] (detection mode) position before closing thefront cover.
Closing the front cover may damage the chamber if the chamber switching unit is not at the [D](detection mode) position.

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7. Maintenance

7-6 Adjusting the flow

7-6 Adjusting the flow
The flow of this product is automatically adjusted by the automatic flow adjuster function to 0.6 L/min ±10 % (0.54 - 0.66).
Set the automatic flow adjuster function to OFF to adjust the flow manually.

NOTE Set the automatic flow adjuster function ON/OFF in Environmental setting 2. (Refer to ‘7-10-11 Flow
automatic adjustment setting (AT FLOW)’.)

7-6-1 Checking the flow (FLOW)
Display the current flow. The following information is displayed: Ctrl: Automatic flow adjuster function ON/OFF setting(If the automatic flow adjuster function is ON, [Auto] is displayed; if OFF, [Manual] isdisplayed.) Output : The current output ratio LineA : Flow (L/min) in flow passage A
 LineB : Flow (L/min) in flow passage B Total: Total flow (L/min) (total of flow passage A and flow passage B)
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 6 FLOW], then press the TEST/SET key.

2

Check the flow.

Flow automatic
adjustment: ON

3

Press the MODE key.
The display reverts to the [2- 6 FLOW] display.

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Flow automatic
adjustment: OFF7. Maintenance

7-6 Adjusting the flow

NOTE Press the SHIFT key in step 2 while the flow is displayed to view the following information as you
hold down the key.
・ Diag.
: Self-diagnostic function ON/OFF setting
・ Reg.Diag. : Regular self-diagnostic ON/OFF setting

Flow automatic
adjustment: ON

Flow automatic
adjustment: OFF

7-6-2 Manually adjusting the flow (FLOW)
Set the automatic flow adjuster function to OFF to allow manual flow adjustment.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 6 FLOW], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to increase or decrease thepump output so that the flow for [LineA] and [LineB] areeach more than 0.28 L/min.
Pump output increases 0.5 % each time you press the ▲key.
Pump output decreases 0.5 % each time you press the ▼key.

3Press the TEST/SET key.
The pump output is set. The display reverts to the [2- 6 FLOW] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [2- 6 FLOW] display.

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7. Maintenance

7-6 Adjusting the flow

7-6-3 Correcting the flow value (DEF FLOW)
Due to aging deterioration of the flow sensor, inappropriate default settings for flow, etc., an error affecting
the flow display may occur. In such cases, correct the flow display.
Flow value corrections are possible whether the automatic flow adjuster function is set to ON or OFF.
Connect a flowmeter (one that can accurately indicate 0.6 L/min) to this product.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 5 DEF FLOW], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [Pump output UP] or[Pump output DOWN], then press the TEST/SET key.
Select [Pump output UP] to increase pump output.
Select [Pump output DOWN] to decrease pump output.
Increase or decrease the output of the pump and adjust sothat the connected flowmeter indicates 0.6 L/min ± 10 %.

3

Press the ▲ key or ▼ key to select [Flow Adjust], thenpress the TEST/SET key.

The flow value is corrected and the display returns to the [2- 5 DEF FLOW] display.

NOTE By selecting [Flow Default] and pressing the TEST/SET key, you can restore the default correction
coefficient.
 Press the MODE key in step 3 to cancel the settings and return to the [2- 5 DEF FLOW] display.

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7. Maintenance

7-7 Checking setting values (maintenance mode)

7-7 Checking setting values (maintenance mode)
7-7-1 Checking the date last calibrated (LAST CAL)
Display the date on which calibration was last performed for each sensor.
No date is displayed if calibration has not been performed since sensor manufacture.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 3 LAST CAL], then press the TEST/SET key.

2

Check the date last calibrated.
Year
Month:Day
Hours:
Minutes

3

Press the MODE key.
The display reverts to the [2- 3 LAST CAL] display.

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7. Maintenance

7-7 Checking setting values (maintenance mode)

7-7-2 Checking the set potential (E VOLT)This displays the set voltage of the electrochemical type sensor (ESF), or the element voltage of thesemiconductor type sensor (SGF) or hot-wire type semiconductor sensor (SHF).
1

In maintenance mode, press the ▲ key or ▼ key to select[2- 4 E VOLT], then press the TEST/SET key.

2

Check the set potential or element voltage.

3

Press the MODE key.
The display reverts to the [2- 4 E VOLT] display.

7-7-3 Checking the temperature of the detector (TEMP)
1

In maintenance mode, press the ▲ key or ▼ key to select[2- 7 TEMP], then press the TEST/SET key.

2

Check the temperature of the detector.

3

Press the MODE key.
The display reverts to the [2- 7 TEMP] display.

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7. Maintenance

7-8 Setting the initial date of sensor use (S SET)

7-8 Setting the initial date of sensor use (S SET)
Set the date of first use for the sensor.
This setting becomes invalid when the sensor is replaced.
1

In maintenance mode, press the ▲ key or ▼ key to select[2-13 S SET], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

3

Press the TEST/SET key to confirm the sensor.
If the setting for the initial date of sensor use is enabled, thescreen for step 5 is displayed.

4

Press the TEST/SET key to enable the setting for the initialdate of sensor use.

5

Check the initial date of sensor use.

6

Press the MODE key.
The display reverts to the display in step 2.
To continue making settings for other sensors, repeat steps 2 to 6.

7

Press the MODE key after making the settings.
The display reverts to the [2-13 S SET] display.

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7. Maintenance

7-9 Making changes in Environmental setting 1

7-9 Making changes in Environmental setting 1
The following items can be set in Environmental setting 1:
LCD display
2- 9 SETTING1

Setting item

Remarks

Environmental setting 1

SET- 0 INHIBITINHIBIT setting

SET- 1 ALM P

ALARM SETTING

SET- 2 ALM DLY

ALARM DELAY SETTING

SET- 3 MAINTE

Maintenance

SET- 4 F TEST

Fault test

SET- 5 OPT ACTTERMINAL UNIT
SETTING

Refer to ‘8. Replacing and cleaning
parts’.

4-20mA

EA

7-9-1 INHIBIT setting (INHIBIT)
Set ON/OFF for INHIBIT for each sensor.
Set to ON to disable external alarm signal output even when gas concentrations exceed the alarm
setpoints in detection mode. This setting is primarily used when testing and inspecting the product.
When all of the sensors are set to ON, the fault alarms and cautions on the main unit also stop being
issued.
The default setting is OFF.
1

In maintenance mode, press the ▲ key or ▼ key
to select [2- 9 SETTING1], then press the
TEST/SET key.

2

Select [SET- 0 INHIBIT] and press the TEST/SET
key.

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7. Maintenance

7-9 Making changes in Environmental setting 1

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle throughthe following settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to select [OFF] or [ON],then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET- 0 INHIBIT] display.

7

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

NOTE For sensors for which the INHIBIT setting has been
set to ON, when you switch to detection mode, thedisplay alternates between the concentration
display and [INHI.].

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7-9-2 Alarm setpoints (ALM P)
Set the gas alarm setpoints (first alarm setpoint, second alarm setpoint) for each sensor.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 1 ALM P], thenpress the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to set the alarm value for the
first alarm setpoint, then press the TEST/SET key.

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<First alarm setpoint setting>7. Maintenance

6

7-9 Making changes in Environmental setting 1

Press the ▲ key or ▼ key to set the alarm value for thesecond alarm setpoint, then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 6.
7

Press the MODE key after making the settings.
The display reverts to the [SET- 1 ALM P] display.

8

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

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7-9-3 Alarm delay time setting (ALM DLY)
Set the alarm delay time for each sensor.
Set a time (0 - 60 seconds) to temporarily suspend activation to prevent false alarms caused by external
noise.
The default setting is two seconds.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 2 ALM DLY],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to set the alarm delay time,then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.

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6

Press the MODE key after making the settings.
The display reverts to the [SET- 2 ALM DLY] display.

7

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

7-9-4 Fault alarm tests (F TEST)
Perform fault alarm tests for each sensor.
This tests whether a fault alarm is triggered when a fault occurs with this product.

WARNING When you perform fault alarm tests, depending on the setting, the fault contact may be activatedeven when in maintenance mode. Note this when performing this operation.
 The fault alarm test cannot be performed on sensors which have INHIBIT set to ON.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 4 F TEST],then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor to betested.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor to betested.

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5

Press the ▲ key or ▼ key to select [ON], then press the
TEST/SET key.

6

Check to confirm that a fault alarm is triggered, thenpress the TEST/SET key.
When the fault alarm is triggered, the fault lamp (FAULT)
lights up (yellow).

Fault lamp (FAULT)
lights up (yellow)

7

Press the ▲ key or ▼ key to select [OFF], then press the
TEST/SET key.
When the fault alarm is reset, the fault lamp (FAULT) turns
off.

Fault lamp (FAULT)
turns off

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 7.
8

Press the MODE key after making the settings.
The display reverts to the [SET- 4 F TEST] display.

9

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

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7-9-5 Terminal unit settings (OPT ACT)

4-20mAEA

Set whether to enable or disable the terminal unit.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 5 OPT ACT],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.
To enable the terminal unit, set to [ON] and todisable it, set to [OFF].

The display reverts to the [SET- 5 OPT ACT] display.
4

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET- 5 OPT ACT] display.

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7-10 Making changes in Environmental setting 2
The following items can be set in Environmental setting 2:
LCD display
2-10 SETTING2

Setting item

Remarks

Environmental setting 2

SET- 0 ADDRESS

Address setting

SET- 1 DAY TIME

Date/time setting

SET- 2 SUPPRESS

Zero suppression value setting

SET- 3 SUP TYPE

Zero suppression type setting

SET- 4 TEST RLY

Settings for contacts during alarm tests

4-20mAEA

SET- 5 TEST4-20

External output during alarm tests

4-20mAEA

SET- 6 RLY PTRN

Energized/de-energized setting

4-20mAEA

SET- 7 ALM TYPE

Alarm type setting

SET- 8 ALM PTRN

Alarm pattern setting

SET- 9 AL LIMIT

Alarm value limiter setting

SET-10 FLT PTRN

Fault pattern setting

SET-11 AT FLOW

Flow automatic adjustment setting

SET-12 ZERO F

Zero following setting

SET-13 ZERO 24F

24-hour zero follower setting

SET-14 S ASSIST

Sensitivity correction setting

SET-15 MNT OUT

External output in maintenance modesetting

4-20mAEA

SET-16 MA 4-20

External output adjustment

4-20mAEA

SET-17 BK LIGHT

Backlight setting

SET-18 ETHERNETETHERNET settings

SET-19 PUMP CK

Pump drive level diagnostic settings

SET-20 FLT RLY

Setting for the behavior of fault contacts
when flow is low

4-20mAEA

SET-21 FLT OUT

External output during fault setting

4-20mAEA

SET-22 CAU DISP

Caution display setting

SET-23 CAU OUT

Caution output setting

SET-24 GAS NAME

Displayed gas name setting

SET-25 CONTRAST

LCD contrast adjustment

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7-10-1 Date and time setting (DAY TIME)
Sets the date and time (year, month, date, hours, minutes) for the internal clock.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 1 DAY TIME],
then press the TEST/SET key.

3

Press the TEST/SET key.

4

Press the ▲ key or ▼ key to set the last two digits of theyear, then press the TEST/SET key.

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5

Press the ▲ key or ▼ key to set the month, then press
the TEST/SET key.

6

Press the ▲ key or ▼ key to set the day, then press the
TEST/SET key.

7

Press the ▲ key or ▼ key to set the hour (24-hour clock
display), then press the TEST/SET key.

8

Press the ▲ key or ▼ key to set the minutes, then press
the TEST/SET key.

The date/time is set. The display reverts to the[SET- 1 DAY TIME] display.
9

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in each of the date/time settings to revert to the previous setting.
 Press the MODE key in step 3 to cancel the date/time settings and return to the [SET- 1 DAY TIME]
display.

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7-10-2 Zero suppression value setting (SUPPRESS)
Set the zero suppression value for each sensor.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 2 SUPPRESS],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to select the zero suppression
value, then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.

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6

Press the MODE key after making the settings.
The display reverts to the [SET- 2 SUPPRESS] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-3 Zero suppression type setting (SUP TYPE)
Set the zero suppression type for each sensor.
Select one of the following: CUT type ([CUT]): Values exceeding the zero suppression value are shown as is.
 SLOPE type ([SLOPE]): Values exceeding the zero suppression value are smoothed for display.
The default setting is CUT type ([CUT]).
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 SUP TYPE],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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Press the ▲ key or ▼ key to select [CUT] or[SLOPE], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET- 3 SUP TYPE] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10-4 Settings for contacts during alarm tests (TEST RLY)

4-20mAEA

Set the operation of contacts during alarm tests ON or OFF.
Set to ON to allow contacts to operate during alarm tests.
The default setting is OFF.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET
key.

2

Press the ▲ key or ▼ key to select [SET- 4 TEST RLY],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [OFF] or [ON],then press the TEST/SET key.

The display reverts to the [SET- 4 TEST RLY] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET- 4 TEST RLY] display.

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7-10-5 Settings for external output during alarm tests (TEST4-20)
4-20mAEA

Set the external output during alarm tests ON or OFF.
Set to ON to use external output (4 - 20 mA) during alarm tests.
When set to OFF, the output from immediately before the alarm test is maintained.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 5 TEST4-20],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or [OFF],then press the TEST/SET key.

The display reverts to the [SET- 5 TEST4-20] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET- 5 TEST4-20] display.

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7-10-6 Energized/de-energized setting (RLY PTRN)

4-20mAEA

Set energized/de-energized for the first alarm contact, second alarm contact, and fault alarm contact.
Set de-energized ([ND]) or energized ([NE]) for each contact.
 If the setting is de-energized, the relay is energized at an alarm state. (De-energized in normal
conditions)・ With contact a, the setting is open under normal conditions and closed at an alarm state.
・ This behavior is reversed with contact b.
 If the setting is energized, the relay is energized under normal conditions. (De-energized at an alarmstate)
・ When using contact a, it is closed in normal conditions and open at an alarm state.
It is also open when supply of power is stopped.
・ This behavior is reversed with contact b.
The default setting is de-energized ([ND]) for each contact.

<Setting the alarm contacts>
Set the first alarm contact and the second alarm contact for each sensor.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 6 RLY PTRN],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2]⇔[FLT RYL].
Select one of [A1], [A2], [B1], or [B2] here.
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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5

Press the ▲ key or ▼ key to select [ND] or[NE], then press the TEST/SET key.

<First alarm contact setting>

6

Press the ▲ key or ▼ key to select [ND] or[NE], then press the TEST/SET key.

<Second alarm contact setting>

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 6.
7

Press the MODE key after making the settings.
The display reverts to the [SET- 6 RLY PTRN] display.

8

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7. Maintenance

7-10 Making changes in Environmental setting 2<Setting the fault alarm contact>1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Select [SET- 6 RLY PTRN], then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [FLT RLY], thenpress the TEST/SET key.

4

Press the ▲ key or ▼ key to select [ND] or[NE], then press the TEST/SET key.

The display reverts to the display in step 3.
5

Press the MODE key.
The display reverts to the [SET- 6 RLY PTRN] display.

6

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10-7 Alarm type setting (ALM TYPE)
Set the alarm type for each sensor.
When an oxygen deficiency alarm model sensor is fitted, any of H-HH type, L-LL type, or L-H type can beset.
The default setting is H-HH type.

NOTE
 Several alarm type settings are possible for oxygen deficiency specification sensors. For othersensors, it will be H-HH type.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 7 ALM TYPE],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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Press the ▲ key or ▼ key to select [H-HH],[L-LL], or [L-H], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET- 7 ALM TYPE] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10-8 Alarm pattern setting (ALM PTRN)
Set the alarm patterns for the alarm setpoints.
Set to either auto-reset ([NL]) or self-latching ([L]).
The default setting is auto-reset ([NL]).

NOTE The alarm pattern settings will affect how the device behaves. For normal use, leave this setting
unchanged.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 8 ALM PTRN],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [NL] or [L],then press the TEST/SET key.

The display reverts to the [SET- 8 ALM PTRN] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET- 8 ALM PTRN] display.

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7-10-9 Alarm value limiter setting (AL LIMIT)
Set ON/OFF for the alarm point limiter.
The default setting is ON.

NOTE
 The alarm value limiter settings will affect how the device behaves. For normal use, leave thissetting unchanged.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET
key.

2

Press the ▲ key or ▼ key to select [SET- 9 AL LIMIT],then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the [SET- 9 AL LIMIT] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET- 9 AL LIMIT] display.

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7-10-10 Fault pattern setting (FLT PTRN)
Set the fault alarm pattern.
Set to either auto-reset ([NL]) or self-latching ([L]).
The default setting is auto-reset ([NL]).

NOTE The fault pattern settings will affect how the device behaves. For normal use, leave this setting
unchanged.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-10 FLT PTRN],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [NL] or [L],then press the TEST/SET key.

The display reverts to the [SET-10 FLT PTRN] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-10 FLT PTRN] display.

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7-10-11 Flow automatic adjustment setting (AT FLOW)
Set the automatic flow adjuster function ON/OFF.
The automatic flow adjuster function is enabled when set to ON.
The automatic flow adjuster function is disabled when set to OFF to allow manual flow adjustments.
The default setting is ON.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-11 AT FLOW],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the [SET-11 AT FLOW] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-11 AT FLOW] display.

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7-10-12 Zero follower setting (ZERO)
Set ON/OFF for the zero follower function for each sensor. (Refer to ‘6-4-2 Zero follower function’.)The default setting is ON.

NOTE
 Zero follower settings are possible for new ceramic type and electrochemical type detection
principle sensors.

1

In maintenance mode, press the ▲ key or ▼key to select [2-10 SETTING2], then press the
TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-12
ZERO F], then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET-12 ZERO F] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-13 24-hour zero follower settings (ZERO 24F)
Set ON/OFF for the 24-hour zero follower function for each sensor. (Refer to ‘6-4-2 Zero follower
function’.)The default setting is ON.

NOTE
 The 24-hour zero follower settings are possible for new ceramic type and electrochemical typedetection principle sensors.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-13 ZERO 24F],
then press the TEST/SET key.

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3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET-13 ZERO 24F] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10-14 Sensitivity correction settings (S ASSIST)
Set ON/OFF for the sensitivity correction function for each sensor. (Refer to '6-4-3 Sensitivity correction
function’.)The default setting is ON.

NOTE
 The sensitivity correction settings are possible for electrochemical type detection principle sensors.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-14 S ASSIST],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.

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6

Press the MODE key after making the settings.
The display reverts to the [SET-14 S ASSIST] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-15 External output in maintenance mode setting (MNT OUT)
4-20mAEA

Make settings for external output in maintenance mode for each sensor.
Select one of the following: 2.5 mA ([2.5]): Set the external output value to 2.5 mA.
 4 - 20 mA ([4-20]) : Set the external output value to 4 - 20 mA (linked to the display value).
 HOLD ([HOLD]) : Value from immediately prior to detection mode is held.
 4.0 mA ([4.0]): Set the external output value to 4.0 mA.
The default setting is 2.5 mA ([2.5]).
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-15 MNT OUT],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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Press the ▲ key or ▼ key to select [2.5], [4-20],[HOLD], or [4.0], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 5.
6

Press the MODE key after making the settings.
The display reverts to the [SET-15 MNT OUT] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10 Making changes in Environmental setting 2

7-10-16 External output adjustment (MA 4- 20)

4-20mA

EA

Adjust the external output of 4 mA and 20 mA for each sensor.
Connect the device signal cable to an ammeter.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-16 MA 4-20],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

5

Press the ▲ key or ▼ key to adjust the output (%).
Confirm that the ammeter reading is 4 mA and press the
TEST/SET key.

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<4 mA adjustment>

7. Maintenance6

7-10 Making changes in Environmental setting 2

Press the ▲ key or ▼ key to adjust the output (%).
Confirm that the ammeter reading is 20 mA and press
the TEST/SET key.

<20 mA adjustment>

The display reverts to the display in step 3.
To continue making adjustments for other sensors, repeat steps 3 to 6.
7

Press the MODE key after making the settings.
The display reverts to the [SET-16 MA 4-20] display.

8

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-17 Backlight setting (BK LIGHT)
Set ON/SAVE for the LCD backlight.
The backlight will remain lit if this is set to ON.
When set to SAVE, the backlight will illuminate only in the event of an operation/event.
The default setting is ON.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-17 BK LIGHT],
then press the TEST/SET key.

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7. Maintenance3

7-10 Making changes in Environmental setting 2

Press the ▲ key or ▼ key to select [ON] or[SAVE], then press the TEST/SET key.

The display reverts to the [SET-17 BK LIGHT] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-17 BK LIGHT] display.

7-10-18 ETHERNET settings (ETHERNET)

ET

EA

Make ETHERNET settings.
Make the following settings.
• [IP Address]: Set the IP address.
• [Subnet Mask]: Set the subnet mask.
• [Default Gateway] : Set the default gateway.
• [DHCP]: Set DHCP ON/OFF.
The IP address is acquired automatically from the DHCP server if [ON] is
selected. [IP Address], [Subnet Mask], and [Default Gateway] settings are notused in this case.
• [PLC Mode]: Set the PLC mode.
• [PLC Area]: Set the PLC area.

NOTE [MAC Address] is an identification number unique to the device. This setting cannot be changed.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

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7. Maintenance

7-10 Making changes in Environmental setting 2

2

Press the ▲ key or ▼ key to select [SET-18 ETHERNET],
then press the TEST/SET key.

3

Select [IP Address], then press the TEST/SET key.

4

Press the ▲ key or ▼ key to set the IP address, thenpress the TEST/SET key.
Repeat step 4 to set each of the numerals for the IP
address.

5

Press the ▲ key or ▼ key to select [Subnet Mask], thenpress the TEST/SET key.

6

Press the ▲ key or ▼ key to set the subnet mask, thenpress the TEST/SET key.
Repeat step 6 to set each of the numerals for the subnet
mask.

7

Press the ▲ key or ▼ key to select [Default Gateway],then press the TEST/SET key.

8

Press the ▲ key or ▼ key to set the default gateway,
then press the TEST/SET key.
Repeat step 8 to set each of the numerals for the default
gateway address.

9

Press the ▲ key or ▼ key to select [DHCP], then press
the TEST/SET key.

10 Press the ▲ key or ▼ key to select [ON] or [OFF], thenpress the TEST/SET key.

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7-10 Making changes in Environmental setting 2

11 Press the ▲ key or ▼ key to select [PLC Mode], thenpress the TEST/SET key.
12 Press the ▲ key or ▼ key to set the PLC mode, thenpress the TEST/SET key.

13 Press the ▲ key or ▼ key to select [PLC Area], thenpress the TEST/SET key.
14 Press the ▲ key or ▼ key to set the PLC area, thenpress the TEST/SET key.

15 Press the MODE key.
The display reverts to the [SET-18 ETHERNET] display.
16 Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in each of the ETHERNET settings to revert to the previous setting.

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7-10 Making changes in Environmental setting 2

7-10-19 Pump drive level diagnostic settings (PUMP CK)Set ON/OFF for pump drive level diagnostics.
Set to ON to run periodic diagnostics on pump drive levels.
The default setting is ON.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-19 PUMP CK],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the [SET-19 PUMP CK] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-19 PUMP CK] display.

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7. Maintenance

7-10 Making changes in Environmental setting 2

7-10-20 Setting for the behavior of fault contacts when flow is low
EA(FLT RLY) 4-20mA
Set the operation of fault contacts when flow is low ON or OFF.
When set to ON, fault contacts operate when the flow is low.
The default setting is ON.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-20 FLT RLY],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the [SET-20 FLT RLY] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-20 FLT RLY] display.

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7-10 Making changes in Environmental setting 2

7-10-21 External output during fault setting (FLT OUT)
Set the external output when there is a fault for each sensor.
Select one of the following: 0.5 mA ([0.5]): Set the external output value to 0.5 mA.
 21.5 mA ([21.5]) : Set the external output value to 21.5 mA.
 OPT ([OPT]): Set in the range between 0.0 mA and 4.0 mA. (digit: 0.1)
The default setting is 0.5 mA ([0.5]).
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-21 FLT OUT],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle through thefollowing settings: [A1]⇔[A2]⇔[B1]⇔[B2].
The setting value for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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4-20mA

EA

7. Maintenance5

7-10 Making changes in Environmental setting 2

Press the ▲ key or ▼ key to select [0.5], [21.5],or [OPT], then press the TEST/SET key.
If you select [OPT], press the ▲ key or ▼ key to
set the external output value, then press the
TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other sensors, repeat steps 3 to 6.
6

Press the MODE key after making the settings.
The display reverts to the [SET-21 FLT OUT] display.

7

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-22 Caution display setting (CAU DISP)
Set whether to display cautions on the LCD.
Set ON/OFF for the following cautions:
For more information on each caution, refer to ‘10. Troubleshooting’.
 E-8X (E-80, E-81, E-82)
 E- 9 E- 6
 E-94
 E-5X (E-50, E-56, E-57, E-58, E-59)
 E-15
 E-83
 E-84
 E-98The default settings are as follows:
EA models, ET models: All cautions are ON
4 - 20 mA models: [E- 6] is OFF, all others are ON

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7-10 Making changes in Environmental setting 2

1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-22 CAU DISP],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the fault code, thenpress the TEST/SET key.

4

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other fault codes, repeat steps 3 to 4.
5

Press the MODE key after making the settings.
The display reverts to the [SET-22 CAU DISP] display.

6

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7. Maintenance

7-10 Making changes in Environmental setting 2

7-10-23 Caution output setting (CAU OUT)
Set whether to externally output cautions.
Set ON/OFF for the following cautions.
For more information on each caution, refer to ‘10. Troubleshooting’.
 E-8X (E-80, E-81, E-82)
 E- 9 E- 6
 E-94
 E-5X (E-50, E-56, E-57, E-58, E-59)
 E-15
 E-83
 E-84
 E-98The default settings are as follows:
EA models, ET models: All cautions are ON
4 - 20 mA models: [E- 6] is OFF, all others are ON
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-23 CAU OUT],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the fault code, thenpress the TEST/SET key.

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7. Maintenance4

7-10 Making changes in Environmental setting 2

Press the ▲ key or ▼ key to select [ON] or[OFF], then press the TEST/SET key.

The display reverts to the display in step 3.
To continue making settings for other fault codes, repeat steps 3 to 4.
5

Press the MODE key after making the settings.
The display reverts to the [SET-23 CAU OUT] display.

6

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

7-10-24 Displayed gas name setting (GAS NAME)
Set the gas name displayed on the LCD for each sensor.
Gas names can be up to eight characters in length.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-24 GAS NAME],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to select the sensor.
Press the ▲ key or ▼ key repeatedly to cycle
through the following settings: [A1]⇔[A2]⇔[B1]⇔[B2].
[----] for the selected sensor blinks.

4

Press the TEST/SET key to confirm the sensor.

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7-10 Making changes in Environmental setting 2

5

Press the TEST/ SET key or MODE key to move thecursor.
To move to the next character, press the TEST/SET key.
To move to the previous character, press the MODE key.

6

Press the ▲ key or ▼ key to select the character, thenpress the TEST/SET key.
Press the ▲ key or ▼ key repeatedly to cycle throughcharacter types: numbers (0 - 9), letters (A - Z), "－" (bar),and the space character.
Press the SHIFT key to switch between upper and lower
case.

7

Repeat steps 5 and 6. Move the cursor to the end of line
after making the settings, then press the TEST/SET key.

The display reverts to the display in step 3.
The display will also return to the display in step 3 after you move the cursor to the beginning of theline and press the MODE key.
To continue to set the gas names for other sensors, repeat steps 3 to 7.
8

Press the MODE key after making the settings.
The display reverts to the [SET-24 GAS NAME] display.

9

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

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7-10 Making changes in Environmental setting 2

7-10-25 LCD contrast adjustment (CONTRAST)
Adjust the contrast of the LCD.
1

In maintenance mode, press the ▲ key or ▼ key to select[2-10 SETTING2], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET-25 CONTRAST],
then press the TEST/SET key.

3

Press the ▲ key or ▼ key to adjust contrast, then press
the TEST/SET key.

The display reverts to the [SET-25 CONTRAST] display.
4

Press the MODE key.
The display reverts to the [2-10 SETTING2] display.

NOTE Press the MODE key in step 3 to cancel the settings and return to the [SET-25 CONTRAST] display.

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8. Replacing and cleaning parts

8-1 Replacing consumable parts

8

Replacing and cleaningparts
8-1 Replacing consumable parts
The sensors and dust filters are consumables.
Replace them when needed based on operating conditions.

8-1-1 Replacing sensors
If the main unit is running, stop the pump and fan before replacing the sensors.
1

In maintenance mode , press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 MAINTE],
then press the TEST/SET key.
The pump and fan stop.

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8. Replacing and cleaning parts

8-1 Replacing consumable parts

3

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther to open to 180°.

4

Loosen the four white knurled screws on thechamber unit.

5

Grasp the projections on the left and right ofthe chamber unit. Pull towards you and lower
to open.

Chamber unit
projection

6

Press the ▲ key or ▼ key to select the sensor
to replace, then press the TEST/SET key.
Multiple sensors can be selected.
Pressing the ▼ key with the [B2] sensor selected
will initiate suction of all gases. Do not press the ▼key while the [B2] sensor is selected until you havereturned the chamber unit to its original position.

The following information is displayed, dependingon the status of the selected sensor:
・ [Not any]:
Not connected
・ [Dummy]:
Dummy connection
・ [C-01][C-02]: The sensor was replaced.
・ [C-03][C-04]: Problem with sensor combination or
the sensor is incompatible.
・ [USED]:The sensor may be older than the one
previously fitted.
・ [COMB]:
Problem with sensor combination

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Chamber unit
projection

8. Replacing and cleaning parts

8-1 Replacing consumable parts

7

Remove the sensor.
Remove the sensor fitted to the position selected instep 6.
The LEDs for sensors that can be removed will turn off.
Grasp the cylindrical part of the sensor and pull out.

8

Attach the new sensor.
Grasp the cylindrical part of the sensor. Match the face ofthe connector on the main unit and the connector on thesensor, then push in firmly to secure in place.
Avoid pressing on the top of the sensor while doing this.
Doing so may damage the sensor.
The LED lights up (green) to indicate the sensor is
attached.
In the screen for step 6, confirm that there are no
problems with the sensor replacement.

9

Return the chamber unit to its original position.

10 Tighten the four white knurled screws on thechamber unit.
Tighten the knurled screws so that the chamber
unit is secured in place.
Gas leaks may result if the knurled screws are nottightened properly.

11 Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.
12 Select the [B2] sensor and press the ▼ key.

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LED for confirming fitted status

8. Replacing and cleaning parts

8-1 Replacing consumable parts

The pump and fan restart. The sensor reconnection andsensor combinations are confirmed.

13 Press the TEST/ SET key when the screen indicatessensor replacement is complete.
The display reverts to the [SET- 3 MAINTE] display.
If replacement was not completed properly, refer to ‘<Ifsensors couldn't be replaced correctly>’ in this section.

14 Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

CAUTION To attach the sensor to the main unit, match the face of the connector on the main unit and theconnector on the sensor, then push in firmly to secure into place. Improper attachment may cause
the sensor to fall out and damage the connector.
 Perform calibration (zero calibration, span adjustment) after sensor replacement.

NOTE
 Press the SHIFT key in the screen for selecting thesensor in step 6 to display information on thesensor just replaced.

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8. Replacing and cleaning parts

8-1 Replacing consumable parts<If sensors couldn't be replaced correctly>
Depending on the problem, one of the following screens will appear if sensor replacement was
unsuccessful: If sensor was not replaced
Press the TEST/SET key so the display returns to the [SET- 3
MAINTE] display.
The pump and fan will restart.

 Problem with sensor combination or incompatible
sensor
It is not possible to return to detection mode. Confirm
the sensor combination (sequence) and contact oursales department.

NOTE
 If the screen indicates a problem with the sensor combination, press theSHIFT key to determine if you can fix the problem by swapping the sensors
within the same flow passage. If this is possible, an example of sensor
combinations will be displayed.

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8. Replacing and cleaning parts

8-1 Replacing consumable parts

8-1-2 Dust filter replacement
Check to confirm that the dust filters are neither dirty nor clogged. Replace, if necessary.
If the main unit is running, stop the pump and fan before replacing the dust filter.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 MAINTE],
then press the TEST/SET key.
The pump and fan stop.

3

Remove the dust filter fitted to the GAS IN side of themain unit.
The dust filter varies depending on the operating
environment.

4

Fit a new dust filter to the GAS IN side of the main unit.

5

Once replacement is complete, press the MODE key.
The display returns to the [SET- 3 MAINTE] display. The pump and fan will restart.

6

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.
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8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

8-2 Replacing periodic replacement parts
8-2-1 List of recommended periodic replacement parts
No.

Name

Check interval

1
2
3

Pump unit
Flow sensor unit
Fan unit

0.5 years
1 year
0.5 years

Replacement
interval
1 - 2 years
5 years
2 - 4 years

Quantity(piece/unit)
11
1

8-2-2 Pump unit replacement
If the main unit is running, stop the pump and fan before replacing the pump unit.

NOTE Before fitting the pump unit, confirm that the pumpunit connections (flow passages) are free of dirt orother foreign matter. The grease applied to theconnecting parts attracts dirt.

Connecting parts(flow passages)

1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 MAINTE],
then press the TEST/SET key.
The pump and fan stop.

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8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

3

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther to open to 180°.

4

Push in on the part indicated with “PUSH” on the
top of the pump unit, then pull the pump unit
forward.

5

Match the new pump unit to the shape of the main unit
and push into place.
Match the projections on the pump unit with thegrooves on the main unit, then push in. Press thecenter of the pump unit, pushing it so that thepump unit is secured properly.

Press in thecenter6

Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.

7

Once replacement is complete, press the MODE key.
The display returns to the [SET- 3 MAINTE] display. The pump and fan will restart.

8

Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

NOTE When pressing the pump unit into the main unit, do
not press on the diaphragms on the sides of thepump unit.

Do not press onthese parts

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8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

8-2-3 Flow sensor unit replacement
If the main unit is running, stop the pump and fan before replacing the flow sensor unit.

1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 MAINTE],
then press the TEST/SET key.
The pump and fan stop.

3

Pull the projection on the top of the main unit
towards you to open the front cover.
The front cover opens to approximately 120°. Pushfurther to open to 180°.

4

Loosen the four white knurled screws on thechamber unit.

5

Grasp the projections on the left and right ofthe chamber unit. Pull towards you and lower
to open.

Chamber unit
projection

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Chamber unit
projection

8. Replacing and cleaning parts

6

8-2 Replacing periodic replacement parts

Unscrew the one screw securing the flow sensor unit.

Flow sensor unit

7

Grasp the projections on the left and right of the flow
sensor unit and pull out.

Flow sensor unit projections

8

Disconnect cable A and cable B connectedto the two connectors on the flow sensor
unit.
Pulling the cable with excessive force may
break the cable. Do not use undue force.

9

Connect cable A and cable B to the twoconnectors on the new flow sensor unit.
Connect cable A to the A side on the flow
sensor unit, and connect cable B to the B side.
You can confirm the A side and B side of theflow sensor unit with the printed guide on top.

Cable A

10 Match the flow sensor unit to the shape of the main unit
and push into place.
Fit to the main unit while taking care not to pinch
the flow sensor unit cable.
11 Use one screw to secure the flow sensor unit.
Confirm that the flow sensor unit is firmly secured.
Gas leaks may result if it is not firmly secured.

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Cable B

8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

12 Return the chamber unit to its original position.
13 Tighten the four white knurled screws on thechamber unit.
Tighten the knurled screws so that the chamber
unit is secured in place.
Gas leaks may result if the knurled screws are nottightened properly.

Chamber unit

14 Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.
15 Once replacement is complete, press the MODE key.
The display returns to the [SET- 3 MAINTE] display. The pump and fan will restart.
16 Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

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8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

8-2-4 Fan unit replacement
If the main unit is running, stop the pump and fan before replacing the fan unit.
1

In maintenance mode, press the ▲ key or ▼ key toselect [2- 9 SETTING1], then press the TEST/SET key.

2

Press the ▲ key or ▼ key to select [SET- 3 MAINTE],
then press the TEST/SET key.
The pump and fan stop.

3

Pull the projection on the top of the main unit towards
you to open the front cover.
The front cover opens to approximately 120°. Pushfurther to open to 180°.

4

Disconnect the fan unit connector on the left side of thefront of the main unit.

5

Pull the fan unit cable out of the groove in the main unit.

6

Grasp by the grips on the left and right of the
fan unit and pull out.

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Grips on the left
and right

8. Replacing and cleaning parts

8-2 Replacing periodic replacement parts

7

Match the fan unit to the shape of the main unit andpush into place.
Grasp by the grips on the left and right of the fanunit and push in until it is secured to the main unit.

8

Insert the fan unit cable into the groove in themain unit.
Confirm that the cable for the fan unit does notproject from the groove in the main unit whenviewed from the front. Failure to insert the cableproperly may result in disconnection.

Insert so that it does not projectfrom the groove.

9

Connect the fan unit connector to the main unit.

10 Close the front cover on the main unit.
Close the front cover firmly so that it clicks back into place.
11 Once replacement is complete, press the MODE key.
The display returns to the [SET- 1 MAINTE] display and the pump and fan restart.
12 Press the MODE key.
The display reverts to the [2- 9 SETTING1] display.

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8. Replacing and cleaning parts

8-3 Cleaning this product8-3 Cleaning this productClean the product if it becomes excessively dirty.
 Always turn the power OFF before cleaning the product.
 Wipe off any dirt with a dry cloth.
Using water or organic solvents to clean the product may result in malfunctions.
 Use dry air to clean pipes. Pipes with extremely dirty interiors can affect gas detection.

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9. Storage, Relocation, and Disposal

9-1 Procedures for storage or when not used for extended periods

9

Storage, Relocation, andDisposal
9-1 Procedures for storage or when not used for extended
periods
The product must be stored under the following conditions: At normal temperature and humidity in a location not exposed to strong light (e.g., direct sunlight)
 In a location free of gases, solvents, and vapors<Storage conditions (Sensor)>
Model

Storage
Temperature
limit
(°C)
(years)Humidity*(% RH)

Pressure
(kPa)

－

Min

Max

Min

Max

Min

Max

SGF

0.5

-10

40

0

90

80

120

SHF

0.5

-10

40

0

90

80

120

NCF

0.5

-10

40

0

90

80

120

ESF

0.5

-10

40

0

90

80

120

Remarks

・ The sensor must be stored in the specified
packing case.
・ Store in a location not exposed to direct
sunlight.
・ Store in an environment free of corrosive
gas, vibration, and dust.
・ Avoid condensation and moisture.
・ Store in an environment free of gases that
may result in catalyst poisoning (e.g.,silicone, chlorine, sulfur gases).
・ The sensor must be stored in the specified
packing case.
・ Store in a location not exposed to direct
sunlight.
・ Store in an environment free of corrosive
gas, vibration, and dust.
・ Avoid condensation and moisture.
・ Store in an environment free of gases that
may result in catalyst poisoning (e.g.,silicone, chlorine, sulfur gases).

* Maximum humidity corresponds to an absolute humidity of 33 g/m3 (33.6 °C, 90 % RH).

158 / 191

9. Storage, Relocation, and Disposal

9-2 Relocation or reuse

9-2 Relocation or reuse
Before relocating the product, refer to ‘4-1 Installation precautions’ and ‘4-4 Installing the main unit’ for
guidance on the relocation destination. Refer to ‘4-6 Wiring procedure’ and ‘4-7 Pipe installation’ for
information on wiring and pipe installation.
Try to keep the unpowered period as brief as possible during the relocation.

CAUTION Gas calibration must be performed before restarting a product that has been relocated or previously
stopped and stored. Contact our sales department for readjustments, including calibration.

9-3 Product disposal
 Used sensors must be returned to our sales department.
 Avoid direct contact with any fluid that leaks from the electrochemical type sensor (ESF). Place the unit
into a plastic bag. Make sure the fluid cannot leak out.
If fluid leaks from the sensor in the detector head, turn the power OFF and immediately contact oursales department.
 Dispose of the the gas monitor as industrial waste (incombustible) in accordance with local regulations.
 The product contains internal batteries. In the EU, note that disposal of products with built-in batteries
must comply with specific procedures. Contact your nearest sales office for advice.
 In the EU, the built-in battery must be disposed of appropriately if an electrochemical type sensor (ESF)
incorporated into this product is discarded. Contact your nearest sales office for advice.
<Battery built into the electrochemical type sensor (ESF)>
Model

Type

CR1632

Lithium battery

WARNING Never disassemble the sensor.
Electrochemical type sensors (ESF) contain electrolyte. Contact with electrolyte may result in skininflammation. Contact with eyes may result in blindness. Contact with clothing may result in
discoloration or damage to the fabric.
If contact occurs, rinse the area immediately with water.

NOTE Crossed-out recycle dustbin markThis pictogram means batteries must be separated from ordinary waste anddisposed of appropriately.
This pictogram is affixed to products containing batteries to which EU Battery
Directive 2006/66/EC applies. These batteries must be disposed of as
specified by the latest directive.

159 / 191

10. Troubleshooting

10-1 Product abnormalities

10

TroubleshootingThis troubleshooting section does not address causes of all problems that may occur with the product. It
provides brief explanations to assist in determining the causes of common problems.
If you encounter symptoms not addressed here or if problems persist even after taking corrective action,
contact our sales department.

10-1 Product abnormalities<Power source related problems>
Symptom/Display

Cause

Corrective action

The power switch is turnedOFF

Turn the power switch ON.

Power supply circuit
abnormality/instantaneousinterruption

Confirm the voltage for the 24 V DC powersource.
For PoE+ connections, check the function andspecifications of the PoE power hub.
Review your setup and assess the need for an
uninterruptible power source, power line filter, or
insulating transformers.

Incorrect installation of
main unit

When using 24 V DC to power the product,check to confirm that the terminal unit isconnected correctly. If no improvement occurs,
contact our sales department.
If you are using a PoE+ connection, contact oursales department.

Cable problems(damage, loose
connections, short circuits)

Check the wiring for this product and for otherdevices in the vicinity.

Effects of sudden surge
noise

Turn the power OFF and restart.
If similar symptoms recur frequently, takeappropriate measures to address the noise
source.

The power cannot be
turned on.

Abnormal operation

160 / 191

10. Troubleshooting

10-1 Product abnormalities<Sensor abnormalities>
If the category is "fault alarm", the fault lamp (FAULT) either lights or flashes.
Category

Symptom/Display(Fault code)

E-10 F-UNIT

E-18 S ZERO

Fault
Alarm

Cause

Corrective action

The sensor is notconnected orconnected
improperly.

Check to confirm that the sensor is properlyattached and that the connector of the sensor
is properly connected.

There areproblems with
communicatingwith the sensor.

Replace with a new sensor.

Zero drift due tochanges inambient conditions
or deterioration
exceeded the zero
follower function
range.

Perform zero calibration.
Replace the sensor if this happens often evenafter zero calibration.

There is a problem
with the sensor.

Replace with a new sensor.
Avoid handling with bare hands if you see
signs of external damage. Handle carefully.

The sensor has
reached the end ofits service life or isdegraded; or the
output device hasreached the end ofits service life.

Replace with a new sensor.

The temperature
exceeded the
maximum
temperature atwhich the sensor isdesigned tofunction.

Ambient temperatures may exceed
specifications.
Gas detection can still be performed in thisstate, but the sensor will degrade more quickly.
If possible, use within the temperature range
indicated in the specifications.
Replace the sensor if this occurs frequently
even at temperatures within specifications.

A warning was
triggered in thesensor.

Gas detection can still be performed in thisstate, but performance may be impaired.
Replace the sensor as soon as possible.

E-11 SENSOR
E-12 CIRCUIT
E-13 S VOLT
E-14 S E-VOLT
E-15 S K-VOLT
E-16 S E-CUR
E-20 S ROM
E-21 S RAM
E-22 S MEMORY
E-23 S EXT-AD
E-27 S S-VOLT
E-28 S TEMP
E-29 S B-VOLT
E-80
E-81
E-82

Warnings
Display
E-83

C-15
E-84

161 / 191

10. Troubleshooting

10-1 Product abnormalities<Flow abnormalities>
If the category is "fault alarm", the fault lamp (FAULT) either lights or flashes.
Category

Symptom/Display(Fault code)

Cause

Corrective action

The protective rubber
caps are still attached.

Remove the protective rubber caps attached to GAS
IN and GAS OUT.

Pump failure

Replace the pump unit.

Flow loss due toclogged dust filter

Replace the dust filter.

Flow loss due to bentor blocked inlet oroutlet tube.

Fix the problem.

The sensor is notconnected orconnected improperly.

Check to confirm that the sensor is properly attachedand that the sensor connector is connected properly.

Flow sensor wire
breaks or faulty
connection.

Contact our sales department.

Flow instability due toimpaired pump
performance

The pump (and pump performance) may be
degraded.
Gas detection can still be performed in this state.
However, you should replace the pump unit as soon
as possible.

Flow instability due toclogged dust filter

Replace the dust filter.

Flow instability due tobent or blocked inlet oroutlet tube

Fix the problem.

Improper installation of
the chamber unit,
knurled screws nottightened properly

Fasten the chamber unit properly.

The chamber switchingunit is not at the proper
position.

Return the chamber switching unit to the [D](detection mode) position.

Blockage in one of theflow passages

Fix the problem.

An abnormality was
discovered during
routine flow sensor
diagnostics.

The flow sensor performance may be degraded.
Degradation of the flow sensor may result in false
readings (i.e., the flow may be outside the stipulated
range of 0.6 L/min ± 10% (0.54 - 0.66) even if thedisplayed flow is the stipulated value.
It is still possible to detect gases as long as no otherfault alarm such as flow loss occurs. Note that you
must replace the flow sensor to clear this warning.
Contact our sales department.

The difference
between the flow
measured on themain unit and the
Improper flow default
actual flow is beyond setting
specifications.
(0.6 L/m ± 10%(0.54 - 0.66))

The default setting for flow on the main unit may beincorrect.
Use a flowmeter to set the default flow.
(Refer to ‘7-6-3 Correcting the flow value (DEF
FLOW)’.)
Frequent occurrence of these symptoms may
indicate a defective flow sensor. Replace the sensor.
Contact our sales department.

E-51 FLOW
Fault
Alarm

E-52 F SENS 1
E-53 F SENS 2

E-50 FLOW

Warnings
Display

E-56 PATH

E-58 F SENS 1

E-59 F SENS 2-

162 / 191

10. Troubleshooting

10-1 Product abnormalities<System abnormality>
If the category is "fault alarm", the fault lamp (FAULT) either lights or flashes.
Category

Symptom/Display(Fault code)
E-99 B-VOLT

Cause

Corrective action

The power supply voltage
is not within the specified
range of values.
The terminal unit isn’t
connected.

Fault
Alarm

E-96 TERM

Communication problems
between the main unit
and the terminal unit

Check the voltage of the supplied power source.
Check the connections to the terminal unit.
For the ET model, go to maintenance mode and set
the terminal unit to OFF.
(Refer to ‘7-9-5 Terminal unit settings (OPT ACT)’.)

System error in terminal
unit

Contact our sales department.

Problems with ROM,
RAM, or nonvolatilememory in the device

Contact our sales department.

Communication cableproblems

Check the wiring for this product and for related
devices.
For 4 - 20 mA models, set the caution display andcaution output [E-6] to OFF.
(Refer to ‘7-10-22 Caution display setting (CAU
DISP)’ and ‘7-10-23 Caution output setting (CAU
OUT)’.)* The same measures are required if no LAN cable isused with an EA model.

The communication
between the main unit
and the communication
board is faulty

Contact our sales department.
For 4 - 20 mA models, set the caution display andcaution output [E- 6] to OFF.
(Refer to ‘7-10-22 Caution display setting (CAU
DISP)’ and ‘7-10-23 Caution output setting (CAU
OUT)’.)

Effects of external noise

Turn the power OFF and restart.
If similar symptoms recur frequently, take appropriate
measures to address the noise source.

E- 9 RTC

Clock abnormality indeviceSet the date and time.
Corrections may not work if the sensitivity correction
function is enabled.
(Refer to ‘7-10-1 Date and time setting (DAY TIME)’.)
Frequent occurrence of these symptoms may indicate
a defective internal clock. Replace the internal clock.
Contact our sales department.

E-94 FLASH

Problem with device flash
memoryGas detection can still be performed in this state, butsome internal data logging functions may not function
properly.
Contact our sales department.

Problem with device fanHigh internal temperatures may reduce service life.
Check to confirm that the connector for the fan unit isproperly connected. Replace the fan unit, if
necessary.
If there is no improvement, contact our sales
department.

E-90 ROM
E-91 RAME-92 MEMORY

E- 6 COMM

Warnings
Display

E-98 FAN

163 / 191

10. Troubleshooting

10-2 Reading abnormalities

10-2 Reading abnormalities
Symptom

The reading rises (ordrops) and remains
unchanged.

A gas alarm is issued
despite the absence of agas leak or otherabnormalities at thedetection point.

Slow response

Span adjustment is notpossible.

Cause

Corrective action

Sensor drift

Perform zero calibration or air calibration.

Presence ofinterference gases

It is difficult to completely eliminate the effects ofinterference gases such as solvents. Contact Riken
Keiki for information on countermeasures, such as
interference gas removal filters.

Slow leakage

They may be a very small leakage (slow leakage) of
the detection target gas. Leaving this unresolved maylead to hazardous conditions. Take the same action
as for gas alarms.

Environmental
fluctuations

Perform zero calibration or air calibration.
Galvanic cell types in particular are susceptible to theeffects of atmospheric pressure. Zero calibration andair calibration must be performed.

Presence ofinterference gases

It is difficult to completely eliminate the effects ofinterference gases such as solvents. Contact Riken
Keiki for information on countermeasures, such as
interference gas removal filters.

Effects of noise

Turn the power OFF and restart.
If similar symptoms recur frequently, take appropriate
measures to address the noise source.

Sudden environmental
changes

Reading alarms may be triggered by sudden changes
in ambient conditions such as temperature.
The product cannot be used if ambient conditions
fluctuate rapidly and often. Take appropriate action toprevent such changes.

Clogged dust filter

Replace the dust filter.

Bent or blocked inlet
or outlet tube

Fix the problem.

There is condensation
inside the inlet tube.

Fix the problem.

The sensor sensitivity
has degraded.

Replace with a new sensor.

The calibration gas
concentration isinappropriate.

Prepare the correct calibration gas.

The sensor sensitivity
has degraded.

Replace with a new sensor.

164 / 191

11. Product Specifications

11-1 GD-84D-EX Specifications

11

Product Specifications
11-1 GD-84D-EX Specifications
11-1-1 GD-84D-EX-EC
Detection principle
Detection target gas
Concentration display
Detection range
Detection method
Suction flow rate
Alarm setpoints
Power supply
indication
Display items
Alarm accuracy(for identical conditions)
Alarm delay time(for identicalconditions)
Gas alarm typeGas alarm indications
Gas alarm pattern
Gas alarm contact
Fault alarm/selfdiagnosis
Fault alarm indications
Fault alarm patternFault alarm contacts
Contact capacity
Contact cable
Transmission method
Transmission cable
FunctionsPower cable
Power source
Power consumption
Pipe connection
openings
Initialization

Electrochemical type
Toxic gases, oxygen
Full-dot display
Depends on detection target gas
Pump suction type
Total flow rate: approx. 0.6 L/min
Depends on detection target gas
POWER LED lights up (green)
Gas name display, flow display, mode display, communication status display
Within ±30 % of alarm setpoint (depending on detection target gas)
Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas)
(not including piping and communication delays)
Two-stage alarm (L-LL, L-H, or H-HH)
First alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).
Auto-reset or self-latching
No-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
System abnormality, sensor abnormality, flow abnormality, temperature increaseabnormality
FAULT LED lights up (yellow)/information displayed
Auto-reset or self-latching
Overall fault contacts: no-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
24 V DC/0.5 A (resistance load)
CVV or equivalent cable (1.25 mm2, maximum 18 core)
Analog transmission: two-wire analog transmission(4 - 20 mA DC, non-insulated, resistance load 300 Ω or less, including cable resistance)
Analog transmission: CVVS or equivalent shielded cable(1.25 mm2, maximum eight cores)
White backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history
CVV or equivalent cable (1.25 mm2), two-core
24 V DC ± 10 %When 24 V DC is connected: approx. 2.5 W (maximum approx. 7 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds
165 / 191

11. Product Specifications

11-1 GD-84D-EX Specifications

Operating temperature
range
Operating humidity
range
Construction
External dimensions
WeightExterior color-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  190 (H)  146 mm (D) (excluding projections)
Approximately 1.9 kg
Main unit: Black Front door: White<Exterior drawings>

M4 mounting
holeOperatingswitches

Display

M4 mounting
hole<Terminal plate>
1

2

3

＋

-

＋

24 V DC

11

12

A1
ALM1

13

4

5

A1
4 - 20 mA

＋

14

A1
ALM2

15

16

A2
ALM1

6

7

A2
4 - 20 mA

＋

17

19

18

A2
ALM2

8

9

B1
4 - 20 mA

＋

20

B1
ALM1

166 / 191

10B2
4 - 20 mA

21

22

B1
ALM2

23

24

B2
ALM1

25

26

B2
ALM2

27

28

FAULT

11. Product Specifications

11-1 GD-84D-EX Specifications

11-1-2 GD-84D-EX
Detection principle
Detection target gas
Concentration display
Detection range
Detection method
Suction flow rate
Alarm setpoints
Power supply
indication
Display items
Alarm accuracy(for identicalconditions)
Alarm delay time(for identicalconditions)
Gas alarm typeGas alarm indications
Gas alarm pattern
Gas alarm contact

Fault alarm/selfdiagnosis
Fault alarm indications
Fault alarm patternFault alarm contacts

Contact capacity
Contact cable
Transmission method
Transmission cable
FunctionsPower cable
Power source
Power consumption
Pipe connection
openings
Initialization
Operating temperature
range
Operating humidity
range
Construction
External dimensions
WeightExterior color

Electrochemical type, new ceramic type, semiconductor type, hot-wire semiconductor type
Toxic gases, combustible gases, oxygen
Full-dot display
Depends on detection target gas
Pump suction type
Total flow rate: approx. 0.6 L/min
Depends on detection target gas
POWER LED lights up (green).
Gas name display, flow display, mode display, communication status display
Within ±30 % of alarm setpoint (depending on detection target gas and detection principle)
Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas and detection principle)(not including piping and communication delays)
Two-stage alarm (L-LL, L-H, or H-HH)
First alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).
Auto-reset or self-latching
No-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
System abnormality, sensor abnormality, flow abnormality, fan disconnection abnormality,
temperature increase abnormality
FAULT LED lights up (yellow)/information displayed.
Auto-reset or self-latching
Overall fault contacts: no-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
24 V DC/0.5 A (resistance load)
CVV or equivalent cable (1.25 mm2, maximum 18 core)
Analog transmission: two-wire analog transmission(4 - 20 mA DC, non-insulated, resistance load 300 Ω or less, including cable resistance)
Analog transmission: CVVS or equivalent shielded cable(1.25 mm2, maximum eight cores)
White backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history
CVV or equivalent cable (1.25 mm2), two-core
24 V DC ± 10 %When 24 V DC is connected: approx. 8 W (maximum approx. 14 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  190 (H)  146 mm (D) (excluding projections)
Approximately 1.9 kg
Main unit: Black Front door: White

167 / 191

11. Product Specifications

11-1 GD-84D-EX Specifications<Exterior drawings>
M4 mounting
holeOperatingswitches

Display

M4 mounting
hole<Terminal plate>
1

2

3

＋

-

＋

24 V DC

11

12

A1
ALM1

13

4

5

A1
4 - 20 mA

＋

14

A1
ALM2

15

16

A2
ALM1

6

7

A2
4 - 20 mA

＋

17

19

18

A2
ALM2

8

9

B1
4 - 20 mA

＋

20

B1
ALM1

168 / 191

10B2
4 - 20 mA

21

22

B1
ALM2

23

24

B2
ALM1

25

26

B2
ALM2

27

28

FAULT

11. Product Specifications

11-1 GD-84D-EX Specifications

11-1-3 GD-84D-EX-ET-EC
Detection principle

Electrochemical type

Detection target gas

Toxic gases, oxygen
Full-dot display

Concentration display
Detection range

Depends on detection target gas

Detection method

Pump suction type

Suction flow rate

Total flow rate: approx. 0.6 L/min

Alarm setpoints

Depends on detection target gas

Power supply
indication

POWER LED lights up (green)

Display items

Gas name display, flow display, mode display, communication status display

Alarm accuracy(for identicalconditions)

Within ±30 % of alarm setpoint (depending on detection target gas)

Alarm delay time(for identicalconditions)

Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas)
(not including piping and communication delays)

Gas alarm typeTwo-stage alarm (L-LL, L-H, or H-HH)

Gas alarm indicationsFirst alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).

Gas alarm pattern

Auto-reset or self-latching

Gas alarm contact-

Fault alarm/selfdiagnosis

System abnormality, sensor abnormality, flow abnormality, communication abnormality,
temperature increase abnormality

Fault alarm indications

FAULT LED lights up (yellow)/information displayed.

Fault alarm pattern

Auto-reset or self-latching

Fault alarm contacts-

Contact capacity-

Contact cable-

Transmission method

Digital transmission: Ethernet (10BASE-T/100BASE-TX)

Transmission cable

Digital transmission: Cat5e or better Ethernet cable

FunctionsWhite backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history

Power cable

Shared with digital transmission cable

Power source

PoE+ connection

Power consumption
Pipe connection
openings
Initialization
Operating temperature
range
Operating humidity
range
Construction
External dimensions
WeightExterior color

When PoE+ is connected: approx. 3.5 W (maximum approx. 4.5 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  183 (H)  140 mm (D) (excluding projections)
Approximately 1.4 kg
Main unit: Black169 / 191

Front door: White11. Product Specifications

11-1 GD-84D-EX Specifications<Exterior drawings>
M4 mounting
hole*

DisplayM4 screw suppliedwith main unit

* An RJ-45 Ethernet connector is located on the underside of the main unit.

170 / 191

Operatingswitches11. Product Specifications

11-1 GD-84D-EX Specifications

11-1-4 GD-84D-EX-ET
Detection principle

Electrochemical type, new ceramic type, semiconductor type, hot-wire semiconductor type

Detection target gas

Toxic gases, combustible gases, oxygen
Full-dot display

Concentration display
Detection range

Depends on detection target gas

Detection method

Pump suction type

Suction flow rate

Total flow rate: approx. 0.6 L/min

Alarm setpoints

Depends on detection target gas

Power supply
indication

POWER LED lights up (green)

Display items

Gas name display, flow display, mode display, communication status display

Alarm accuracy(for identicalconditions)

Within ±30 % of alarm setpoint(depending on detection target gas and detection principle)

Alarm delay time(for identicalconditions)

Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas and detection principle)(not including piping and communication delays)

Gas alarm typeTwo-stage alarm (L-LL, L-H, or H-HH)

Gas alarm indicationsFirst alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).

Gas alarm pattern

Auto-reset or self-latching

Gas alarm contact-

Fault alarm/selfdiagnosis

System abnormality, sensor abnormality, flow abnormality, communication abnormality, fandisconnection abnormality, temperature increase abnormality

Fault alarm indications

FAULT LED lights up (yellow)/information displayed.

Fault alarm pattern

Auto-reset or self-latching

Fault alarm contacts-

Contact capacity-

Contact cable-

Transmission method

Digital transmission: Ethernet (10BASE-T/100BASE-TX)

Transmission cable

Digital transmission: Cat5e or better Ethernet cable

FunctionsWhite backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history

Power cable

Shared with digital transmission cable

Power source

PoE+ connection

Power consumption
Pipe connection
openings
Initialization
Operating temperature
range
Operating humidity
range
Construction
External dimensions
WeightExterior color

When PoE+ is connected: approx. 9 W (maximum approx. 11 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  183 (H)  140 mm (D) (excluding projections)
Approximately 1.4 kg
Main unit: Black

171 / 191

Front door: White11. Product Specifications

11-1 GD-84D-EX Specifications<Exterior drawings>
M4 mounting
hole*

DisplayM4 screw suppliedwith main unit

* An RJ-45 Ethernet connector is located on the underside of the main unit.

172 / 191

Operatingswitches11. Product Specifications

11-1 GD-84D-EX Specifications

11-1-5 GD-84D-EX-EA-EC
Detection principle
Detection target gas
Concentration display
Detection range
Detection method
Suction flow rate
Alarm setpoints
Power supply
indication
Display items
Alarm accuracy(for identical conditions)
Alarm delay time(for identical conditions)
Gas alarm typeGas alarm indications
Gas alarm pattern
Gas alarm contact

Fault alarm/selfdiagnosis
Fault alarm indications
Fault alarm patternFault alarm contacts

Contact capacity
Contact cable
Transmission method

Transmission cable

FunctionsPower cable
Power source
Power consumption
Pipe connection
openings
Initialization
Operating temperature
range
Operating humidity
range
Construction
External dimensions

Electrochemical type
Toxic gases, oxygen
Full-dot display
Depends on detection target gas.
Pump suction type
Total flow rate: approx. 0.6 L/min
Depends on detection target gas.
POWER LED lights up (green)
Gas name display, flow display, mode display, communication status display
Within ±30 % of alarm setpoint (depending on detection target gas)
Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas)
(not including piping and communication delays)
Two-stage alarm (L-LL, L-H, or H-HH)
First alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).
Auto-reset or self-latching
No-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
System abnormality, sensor abnormality, flow abnormality, communication abnormality,
temperature increase abnormality
FAULT LED lights up (yellow)/information displayed.
Auto-reset or self-latching
Overall fault contacts: no-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
24 V DC/0.5 A (resistance load)
CVV or equivalent cable (1.25 mm2, maximum 18 core)
Digital transmission: Ethernet (10BASE-T/100BASE-TX)
Analog transmission: two-wire analog transmission(4 - 20 mA DC, non-insulated, resistance load 300 Ω or less, including cable resistance)
Digital transmission: Cat5e or better Ethernet cable
Analog transmission: CVVS or equivalent shielded cable(1.25 mm2, maximum eight cores)
White backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history
CVV or equivalent cable (1.25 mm2), two-core(Shared with digital transmission cable when PoE+ connection is used)
24 V DC ± 10 % or PoE+ connection
When 24 V DC is connected: approx. 3 W (maximum approx. 8 W)
When PoE+ is connected approx. 4.5 W (maximum approx. 9.5 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  190 (H)  146 mm (D) (excluding projections)
173 / 191

11. Product Specifications

11-1 GD-84D-EX Specifications

Approximately 1.9 kg
Main unit: Black Front door: White

WeightExterior color<Exterior drawings>
M4 mounting
holeOperatingswitches

Display

M4 mounting
hole* An RJ-45 Ethernet connector is located on the underside of the main unit.

<Terminal plate>
1

2

3

4

5

6

7

8

9

10

＋

-

＋

-

＋

-

＋

-

＋

-

A1
4 - 20 mA

24 V DC*

11

12

A1
ALM1

13

14

A1
ALM2

15

A2
4 - 20 mA

16

A2
ALM1

17

18

A2
ALM2

B1
4 - 20 mA

19

20

B1
ALM1

B2
4 - 20 mA

21

22

B1
ALM2

23

24

B2
ALM1

25

26

B2
ALM2

27

FAULT

* With EA models, do not use 24 V DC terminals 1 and 2 when using the PoE+ connection. (Connection prohibited)

174 / 19128

11. Product Specifications

11-1 GD-84D-EX Specifications

11-1-6 GD-84D-EX-EA
Detection principle
Detection target gas
Concentration display
Detection range
Detection method
Suction flow rate
Alarm setpoints
Power supply
indication
Display items
Alarm accuracy(for identical conditions)
Alarm delay time(for identical conditions)
Gas alarm typeGas alarm indications
Gas alarm pattern
Gas alarm contact

Fault alarm/selfdiagnosis
Fault alarm indications
Fault alarm patternFault alarm contacts

Contact capacity
Contact cable
Transmission method

Transmission cable

FunctionsPower cable
Power source
Power consumption
Pipe connection
openings
Initialization
Operating temperature
range
Operating humidity
range
Construction
External dimensions

Electrochemical type, new ceramic type, semiconductor type, hot-wire semiconductor type
Toxic gases, combustible gases, oxygen
Full-dot display
Depends on detection target gas.
Pump suction type
Total flow rate: approx. 0.6 L/min
Depends on detection target gas.
POWER LED lights up (green)
Gas name display, flow display, mode display, communication status display
Within ±30 % of alarm setpoint(depending on detection target gas and detection principle)
Within 60 seconds after providing gas at 1.6 times the alarm setpoint(depending on detection target gas and detection principle)(not including piping and communication delays)
Two-stage alarm (L-LL, L-H, or H-HH)
First alarm: ALM1 LED lights up (red).
Second alarm: ALM2 LED lights up (red).
Auto-reset or self-latching
No-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
System abnormality, sensor abnormality, flow abnormality, communication abnormality, fandisconnection abnormality, temperature increase abnormality
FAULT LED lights up (yellow)/information displayed.
Auto-reset or self-latching
Overall fault contacts: no-voltage contact 1a or 1b
Always de-energized (energized in alarm state) or always energized(de-energized in alarm state)
24 V DC/0.5 A (resistance load)
CVV or equivalent cable (1.25 mm2, maximum 18 core)
Digital transmission: Ethernet (10BASE-T/100BASE-TX)
Analog transmission: two-wire analog transmission(4 - 20 mA DC, non-insulated, resistance load 300 Ω or less, including cable resistance)
Digital transmission: Cat5e or better Ethernet cable
Analog transmission: CVVS or equivalent shielded cable(1.25 mm2, maximum eight cores)
White backlight, alarm delay, suppression, zero follower, sensitivity correction, flow control,calibration history, alarm trend history, event history
CVV or equivalent cable (1.25 mm2), two-core(Shared with digital transmission cable when PoE+ connection is used)
24 V DC ± 10 % or PoE+ connection
When 24 V DC is connected: approx. 9 W (maximum approx. 15 W)
When PoE+ is connected: approx. 11 W (maximum approx. 16 W)
Rc1/4 (OD φ6-1 t half union for Teflon pipe <PP> supplied）
Approx. 25 seconds-10 – 40 °C (no sudden changes)
20 – 90 % RH (No condensation; may depend on the sensors installed.)
Wall mounting type
Approx. 150 (W)  190 (H)  146 mm (D) (excluding projections)
175 / 191

11. Product Specifications

11-1 GD-84D-EX Specifications

Approximately 1.9 kg
Main unit: Black Front door: White

WeightExterior color<Exterior drawings>
M4 mounting
holeOperatingswitches

Display

M4 mounting
hole* An RJ-45 Ethernet connector is located on the underside of the main unit.

<Terminal plate>
1

2

3

4

5

6

7

8

9

10

＋

-

＋

-

＋

-

＋

-

＋

-

A1
4 - 20 mA

24 V DC*

11

12

A1
ALM1

13

14

A1
ALM2

15

A2
4 - 20 mA

16

A2
ALM1

17

18

A2
ALM2

B1
4 - 20 mA

19

20

B1
ALM1

B2
4 - 20 mA

21

22

B1
ALM2

23

24

B2
ALM1

25

26

B2
ALM2

27

FAULT

* With EA models, do not use 24 V DC terminals 1 and 2 when using the PoE+ connection. (Connection prohibited)

176 / 19128

11. Product Specifications

11-2 Sensor specifications

11-2 Sensor specifications
11-2-1 Electrochemical type
Sensor model
Detection target gas
Detection range

ESF
Toxic gases*1

OxygenDepends on detection target gas.

0 -25 vol%Detection method

Pump suction type

Alarm setpoints

Depends on detection target gas.

18 vol%(default)

Alarm accuracy(for identicalconditions)

Within ±30 % *2

Within ±0.6 vol%Alarm delay time(for identicalconditions)

Within 60 seconds *3

Within 10 seconds *4

Two-stage alarm (H-HH)

Two-stage alarm (L-LL, L-H)

Alarm typeOperatingtemperature range-10 – 40 °C (no sudden changes)

Operating humidity
range

20 – 90 % RH (No condensation) (Specifications differ for certain gases.)*1 The range of operating temperatures and operating humidity may differ depending on the detection target gas.
*2 Indicates the precision against the alarm setpoint.
*3 When gas is provided at 1.6 times the alarm setpoint. (excluding piping and communication delays)*4 This is the time required to reach the 18 vol% alarm point after supplying gas with a concentration of 10 to 11 vol%(excluding piping and communication delays)

NOTE
 Contact Riken Keiki for specifications and information on other sensors.
 The number of years of ESF sensor warranty depends on the sensor model. Please refer to thesensor specification sheet.

177 / 191

11. Product Specifications

11-2 Sensor specifications

11-2-2 New ceramic type
Sensor model
Detection target gas
Detection range
Detection method
Alarm setpoints
Alarm accuracy(for identicalconditions)
Alarm delay time(for identicalconditions)
Alarm typeOperatingtemperature range
Operating humidity
range

NCF
Combustible gas
Depends on detection target gas.
Pump suction type
Depends on detection target gas.
Within ±25 % *1
Within 30 seconds *2
Two-stage alarm (H-HH)-10 – 40 °C (no sudden changes)
Up to 95 % RH (no condensation)*1 Indicates the precision against the alarm setpoint.
*2 When gas is provided at 1.6 times the alarm setpoint. (excluding piping and communication delays)

NOTE

 Install in a stable location within the specified operating temperature range and free of sudden
temperature fluctuations.
 Sensor characteristics may degrade significantly in the presence of silicon gases (organic silicongases), various types of halogen gases, sulfide gases, or acidic gases.
 When calibrating, allow the product to warm up for at least two hours in clean air before proceedingwith zero calibration and span adjustment.
 For specifications of F.S. 5,000 ppm or less, variations in atmospheric temperature and humidity
may cause the zero point to drift. If so, turn the zero follower function ON. However, we recommend
using a sensor with a different detection principle. The zero follower function is not available if gases
are always present.
 Readings may be affected by combustible gases other than the detection target gas.
 When oxygen concentrations fall, the readings may also fall.
 Some interference may occur in the presence of highly thermally conductive gases such as CO2, Ar,
and He in high concentrations as base gases.
 When low vapor pressure gases are detected by aspiration, the gas may condense when aspirated
from warmer areas and detected in cooler areas, or blockages may occur in sintered alloy. Keepvapor pressure in mind when using the product.
 Indication accuracy may degrade in situations in which temperatures fluctuate significantly (±40 °C
or greater) above or below the ambient temperature in which zero calibration or span adjustment
was performed. If this occurs, repeat the zero calibration or span adjustment.
 There may be fluctuations in readings if the product is subjected to strong impact or vibrations. If
this occurs, perform zero calibration and span adjustment.
 The zero point may fluctuate if the sensor is in continuous contact with high-concentration gas of
100 % LEL or more for extended periods. If this occurs, perform zero calibration and span
adjustment.
 The sensor may be hot during replacement. Be careful to avoid burns when replacing the sensor. If
the sensor is hot, turn off the power and wait for it to cool.
 The tops of the sensors are covered with a Teflon film. Damage to this Teflon film may affect theperformance of the sensor. Avoid applying excessive pressure or sharp objects to the Teflon film.
 When changing to an NCF sensor of different specifications, change the specifications of thedetector with sensors other than NCF sensor fitted before fitting the NCF sensor with desired
specifications.
 Regardless of the detection target gas, the warranty period for NCF sensors is 3 years.

178 / 191

11. Product Specifications

11-2 Sensor specifications

11-2-3 Semiconductor type
Sensor model
Detection target
gas

SGF
Combustible gas

Toxic gas

Detection range

Depends on detection target gas.

Detection method

Pump suction type

Alarm setpoints

Depends on detection target gas.

Alarm accuracy(for identicalconditions)

Within ±25 %Within ±30 %Alarm delay time(for identicalconditions)

Within 30 seconds

Within 60 seconds

Alarm typeTwo-stage alarm (H-HH)

Operatingtemperature range-10 - 40 °C (no sudden changes)

Operating humidity
range

20 – 90 % RH (No condensation) (moisture content 37 °C 95 % RH or less)

NOTE Sensor characteristics may degrade significantly in the presence of silicon gases (organic silicongases), the various types of halogen gases, sulfide gases, or acidic gases.
 Select the calibration gas after accounting for typical humidity in the operating environment.
 When calibrating, allow a warmup time depending on the unpowered period in clean air before
proceeding with the zero calibration and span adjustment. Refer to <Warmup time forsemiconductor type sensors> below for warmup times.
 Readings may be affected by combustible gases other than the detection target gas.
 Readings may fluctuate in the presence of fluctuations (e.g., temperature and humidity) in the
installation location.
 When oxygen concentrations fall, the readings may also fall.
 Some interference may occur in the presence of highly thermally conductive gases such as CO2, Ar,
and He in high concentrations as base gases.
 When low vapor pressure gases are detected by aspiration, the gas may condense when aspirated
from warmer areas and detected in cooler areas, or blockages may occur in sintered alloy. Keepvapor pressure in mind when using the product.
 Indication accuracy may degrade in situations in which temperatures fluctuate significantly (±40 °C
or greater) above or below the ambient temperature in which zero calibration or span adjustment
was performed. If this occurs, repeat zero calibration or span adjustment.
 There may be fluctuations in readings if the product receives strong shocks from outside or issubjected to vibrations. If this occurs, perform zero calibration and span adjustment.
 The zero point and readings may fluctuate if the sensor comes into contact with high-concentration
gas that is full scale or higher. If this occurs, perform zero calibration and span adjustment.
 Readings may fall in environments where gas is continuously present.
 The sensor may be hot during replacement. Be careful to avoid burns when replacing the sensor. If
the sensor is hot, turn off the power and wait for it to cool.
 There is a Teflon film on the top of the sensors. There may be an impact on the performance of thesensor if this Teflon film is damaged. Avoid applying excessive pressure or sharp objects to the
Teflon film.
 Depending on the conditions and how long the device was off, the reading may oscillate when the
power is turned on. The reading should quickly stabilize at zero.
 Regardless of the detection target gas, the warranty period for SGF sensors is 3 years.

179 / 191

11. Product Specifications

11-2 Sensor specifications<Warmup time for semiconductor type sensors>
Unpowered period

Warmup time
SGF-8581

Other SGF sensors

Within 10 minutes

2 hours or more

30 minutes or more

Within 1 hour

2 hours or more

2 hours or more

Within 24 hours

4 hours or more

4 hours or more

Within 72 hour

24 hours or more

24 hours or more

Within 10 days

2 days or more

2 days or more

Less than 1 month

7 days or more

7 days or more

1 month to less than 3months14 days or more

14 days or more

3 months or more

1 month or more

1 month or more

<Definition of combustible gas> All sensor models of %LEL (vol%) range and ppm range specifications are applicable to the following 12
gases.
Acetylene, isobutane, LPG, LNG, ethane, ethylene, hydrogen, town gases, butane, propane, propylene,
and methane Sensors of the %LEL (vol%) range specification are applicable to other combustible gases.
<Definition of toxic gas> Regard gases not included on List A as toxic gases.

180 / 191

11. Product Specifications

11-2 Sensor specifications

11-2-4 Hot-wire semiconductor type
Sensor model
Detection target
gas

SHF
Combustible gas

Toxic gas

Detection range

Depends on detection target gas.

Detection method

Pump suction type

Alarm setpoints

Depends on detection target gas.

Alarm accuracy(for identicalconditions)

Within ±25 %Within ±30 %Alarm delay time(for identicalconditions)

Within 30 seconds

Within 60 seconds

Alarm typeTwo-stage alarm (H-HH)

Operatingtemperature range-10 - 40 °C (no sudden changes)

Operating humidity
range

20 - 90 % RH (No condensation) (moisture content 37 °C 95 % RH or less)

NOTE Sensor characteristics may degrade significantly in the presence of silicon gases (organic silicongases), the various types of halogen gases, sulfide gases, or acidic gases.
 Select the calibration gas after accounting for typical humidity in the operating environment.
 When calibrating, allow a warmup time depending on the unpowered period in clean air before
proceeding with the zero calibration and span adjustment. Refer to <Warmup time for hot-wiresemiconductor type sensors> below for warmup times.
 Readings may be affected by combustible gases other than the detection target gas.
 Readings may fluctuate in the presence of fluctuations (e.g., temperature and humidity) in the
installation location.
 When oxygen concentrations fall, the readings may also fall.
 Some interference may occur in the presence of highly thermally conductive gases such as CO2, Ar,
and He in high concentrations as base gases.
 When low vapor pressure gases are detected by aspiration, the gas may condense when aspirated
from warmer areas and detected in cooler areas, or blockages may occur in sintered alloy. Keepvapor pressure in mind when using the product.
 Indication accuracy may degrade in situations in which temperatures fluctuate significantly (±40 °C
or greater) above or below the ambient temperature in which zero calibration or span adjustment
was performed. If this occurs, repeat zero calibration or span adjustment.
 There may be fluctuations in readings if the product receives strong shocks from outside or issubjected to vibrations. If this occurs, perform zero calibration and span adjustment.
 The zero point may fluctuate if the sensor comes into contact with high-concentration gas
continuously for extended periods. If this occurs, perform zero calibration and span adjustment.
 Readings may fall in environments where gas is continuously present.
 The sensor may be hot during replacement. Be careful to avoid burns when replacing the sensor. If
the sensor is hot, turn off the power and wait for it to cool.
 Depending on the conditions and how long the device was off, the reading may oscillate when the
power is turned on. The reading should quickly stabilize at zero.
 Regardless of the detection target gas, the warranty period for SHF sensors is 3 years.

181 / 191

11. Product Specifications

11-2 Sensor specifications<Warmup time for hot-wire semiconductor type sensors>
Warmup time
Unpowered period*

Other SHF
sensors

SHF-8603

Within 10 minutes

10 minutes ormore

1 hours or more

Within 1 hour

30 minutes ormore

2 hours or more

Within 24 hours

1 hour or more

4 hours or more

Within 72 hours

4 hours or more

24 hours or more

Within 10 days

2 days or more

2 days or more

Less than 1 month

7 days or more

7 days or more

1 month to less than 3 months

14 days or more

14 days or more

3 months or more

1 month or more

1 month or more

Note that the warmup time for SHF-8603 differs from that for other SHF sensor.

<Definition of combustible gas> All sensor models of %LEL (vol%) range and ppm range specifications are applicable to the following 12
gases.
Acetylene, isobutane, LPG, LNG, ethane, ethylene, hydrogen, town gases, butane, propane, propylene,
and methane Sensors of the %LEL (vol%) range specification are applicable to other combustible gases.
<Definition of toxic gas> Regard gases not included on List A as toxic gases.

182 / 191

12. Appendix

12-1 Detection principle

12

Appendix12-1 Detection principle
12-1-1 Electrochemical type
<Sensor overview>
This sensor type detects gas concentrations as current generated when the detection target gas iselectrolyzed on electrodes maintained at constant potential. This is the most effective gas sensor for
detecting toxic gas. Gases can be selectively detected by selecting a specific potential.

<Sensor structure and principle>
 Structure
The sensor consists of an electrode (working electrode) formed of a precious metal catalyst on a gas
permeable membrane, a reference electrode, and a counter electrode, all enclosed in a plastic
container filled with electrolyte solution.
 Principle
A potentiostat circuit is used to maintain constant potential between the working electrode and referenceelectrode. The detection target gas passes through the gas permeable membrane and undergoes
electrolysis reaction on reaching the working electrode. A side reaction also occurs at the counterelectrode so that the same amount of electric current flows through it as that produced at the working
electrode.
Example : In the case of hydrogen sulfide (H2S), the following chemical reaction occurs:
Working electrode: H2S + 4H2O → H2SO4 + 8H+ + 8e- (e- is an electron)
Counter electrode: 2O2 + 8H+ + 8e- → 4H2O
The current generated here is proportional to gas concentrations. Gas concentrations can be
determined by measuring the current flowing through the working electrode.
<Structure diagram>
Potentiostat circuit
Working
electrode

Referenceelectrode

Detection
target gas

ElectrolyteGaspermeable
membrane
Catalyst

Counter
electrodeContainer

183 / 191

12. Appendix

12-1 Detection principle<Points to note when using the electrochemical type sensor>
In particular, note the following points when using the electrochemical type sensor:
1. The product may be subject to interference from solvent vapor or gases other than the target gas.
Take care to avoid alarm activation due to interference. The product may also experience fluctuations
due to environmental changes (e.g., in temperature or humidity) at the location where it is installed.
2. Set the alarm setpoint within the performance range of the device.
In facilities subject to the High Pressure Gas Safety Act, when below the specified Riken Keiki standard
alarm setpoint (maximum allowable concentration) may result in false alarms.
3. The product is a safety device. It is not a control device.
Use the contact outputs on the product with external alarm lamps or buzzers. Use the analog signal
output for indicators or external recorders. Riken Keiki rejects liability for malfunctions in cases in which
this signal is used for any other controls.
4. The contact point of the gas detection sensor consists of a porous polymer membrane. Solvents may
impair the water repellency of the membrane and result in leaking electrolyte.
Avoid using solvents near the detector. If the use of solvents is unavoidable, place our recommended
filter over areas like the gas detector inlet when using solvents and for about one hour thereafter.
5. Regular maintenance is essential, including periodic parts replacement and readjustments as
described in this operating manual. The product is a safety device. We recommend regular
maintenance and gas calibration every six months in accordance with regulations.

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12. Appendix

12-1 Detection principle

12-1-2 New ceramic type
<Sensor overview>The device uses an ultrafine particle (new ceramic) oxidation catalyst to detect gas concentrations over awide range, from low concentrations (ppm) up to the lower explosive limit (LEL). This revolutionary gas
detection sensor was developed by Riken Keiki and designed specifically to detect combustible gases.

<Sensor structure and principle>
 Structure
The new ceramic sensors consist of a detecting element and a compensating element. (Some sensors
lack a compensating element.) The detecting element consists of an ultrafine particle oxidation catalyst(new ceramic) that reacts with combustible gases sintered on top of a precious metal coil. This
undergoes a combustion reaction in the presence of the detection target gas.
The compensating element consists of a material inert to combustible gases sintered on top of a
precious metal coil. This compensates for atmospheric effects.
 Principles
When combustible gas burns on the surface of the detecting element heated to between 300 °C and
450 °C by the precious metal coil, this increases the temperature of the element. The resistance of the
precious metal wire coil forming the element also varies in accordance with this temperature variation.
The resistance variation is roughly proportional to gas concentration. This variation in resistance is thus
extracted as a voltage using a bridge circuit and the gas concentration is worked out.
<Sensor element diagram>Compensating element
・・・Compensates for atmospheric effects

Detecting element
・・・Detects gas
Oxidation catalyst＋
alumina carrier

Glass＋
alumina carrier

Precious metal
wire coil

Precious metal
wire coil
0.5 - 1.4 mm

0.5 - 1.4 mm
0.8 - 1.4 mm

0.8 - 1.4 mm<Bridge circuit>
Element temperature
decreases
Resistancedecreases
Compensating
element

Element temperature
increases
Resistance increases
Detectingelement+
V-

Resistance ofrheostat arm R

Sensor voltage Vs

185 / 191

Sensor output

12. Appendix

12-1 Detection principle<Points to note when using the new ceramic type sensor>
In particular, note the following points when using the new ceramic type sensor:
1. The product may be subject to interference from gases or vapors other than the target gas.
Take care to avoid alarm activation due to interference. The product may also experience fluctuations
due to environmental changes (e.g., in temperature or humidity) at the location where it is installed.
2. The alarm setpoint should be set within the performance range of the device.
In facilities subject to the High Pressure Gas Safety Act, settings below the standard alarm setpoints
specified by Riken Keiki may result in false alarms.
3. The product is a safety device. It is not a control device.
Use the alarm contact outputs on the product with external alarm lamps or buzzers. Use the analog
signal output for indicators or external recorders. Riken Keiki rejects liability for malfunctions in cases inwhich this signal is used for any other controls.
4. The gas sensing parts in the gas detecting sensors of this product are metal-oxide porous sinteredalloys impregnated with oxidation catalysts. The surface area of the gas sensing parts shrinks whensilicone and sulfides attach to the surface of the sintered bodies, and this can cause a large drop in
sensitivity.
For safety reasons, avoid using this product in environments containing even trace amounts of silicone
or sulfides.
5. Regular maintenance is essential, including periodic parts replacement and readjustments as
described in this operating manual. The product is a safety device. We recommend regular
maintenance and gas calibration every six months in accordance with regulations.

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12. Appendix

12-1 Detection principle

12-1-3 Semiconductor type
<Sensor overview>
This method detects gas concentrations from variations in resistance that occur when a metal oxide
semiconductor comes into contact with the detection target gas. This general-purpose gas detector sensor
is ideal for detecting a wide range of gases, from toxic gases to combustible gases.

<Sensor structure and principle>
 Structure
The sensor consists of a metal oxide semiconductor (SnO2) formed around a heater coil and alumina
tube. The alumina tube has two gold electrodes at each end to measure semiconductor resistance.
 Principle
Oxygen from the atmosphere is adsorbed as O- and O2- to the surface of the metal oxide semiconductor
heated to between 350 °C and 400 °C by the heater coil. The semiconductor maintains a constantresistance. If a methane or other such gas comes into contact with this surface and becomes chemicallyadsorbed, the oxygen is oxidized and released by the adsorbed O2- ions.
The following chemical reaction occurs here at the sensor surface:
CH4 ＋ 4O2- → CO2 ＋ 2H2O ＋ 8eIn other words, as methane gas is adsorbed to the sensor surface removing adsorbed oxygen, theincrease in free electrons inside the sensor reduces the resistance. This variation in resistance can bemeasured and used to calculate the gas concentration.
<Sensor element diagram>

Gold electrodes

Metal oxide
semiconductor<Drive circuit>

DC power
sourceZero calibrator
Detectingelement

Heater coil
Alumina tube

Signal amplifier

Indicator

Lead wires
HeaterVoltageregulator

H2O

H2Span adjuster

H2 ＋ O2- → H2O ＋ 2e-

187 / 191

12. Appendix

12-1 Detection principle<Points to note when using the semiconductor type sensor>
In particular, note the following points when using the semiconductor type sensor:
1. The product may be subject to interference from gases or vapors other than the target gas.
Take care to avoid alarm activation due to interference. The product may also experience fluctuations
due to environmental changes (e.g., in temperature or humidity) at the location where it is installed.
2. The alarm setpoint should be set within the performance range of the device.
In facilities subject to the High Pressure Gas Safety Act, settings below the standard alarm setpoints
specified by Riken Keiki may result in false alarms.
3. The product is a safety device. It is not a control device.
Use the alarm contact outputs on the product with external alarm lamps or buzzers. Use the analog
signal output for indicators or external recorders. Riken Keiki rejects liability for malfunctions in cases inwhich this signal is used for any other controls.
4. The gas sensing parts in the gas detecting sensors of this product are metal-oxide porous sinteredalloys. The surface area of the gas sensing parts shrinks when silicone and sulfides attach to thesurface of the sintered bodies, and this can cause a large drop in sensitivity.
For safety reasons, avoid using this product in environments containing even trace amounts of silicone
or sulfides.
5. Regular maintenance is essential, including periodic parts replacement and readjustments as
described in this operating manual. The product is a safety device. We recommend regular
maintenance and gas calibration every six months in accordance with regulations.

188 / 191

12. Appendix

12-1 Detection principle

12-1-4 Hot wire semiconductor type
<Sensor overview>
This sensor type detects gas concentrations based on variations in the resistance of a platinum coil
integrated with a metal oxide semiconductor whose resistance changes when it comes into contact with agas. The high-sensitivity low-concentration detection gas sensor is configured simply as a detecting
element of metal oxide semiconductor sintered around a platinum coil.

<Sensor structure and principle>
 Structure
The sensor consists simply of a detecting element formed of a metal oxide semiconductor sinteredaround a platinum coil.
 Principle
The resistance (R) of the detecting element is the combined resistance of the semiconductor resistance(RS) and the platinum coil resistance (RH).
The detecting element is heated to between 300 °C and 400 °C by the platinum coil and maintains
constant resistance. If methane or another such gas comes into contact with the detecting element,
oxygen adsorbed to the surface of the metal oxide semiconductor is released, increasing the number offree electrons inside the semiconductor and reducing the resistance of the semiconductor. This reduces
the resistance of the entire detecting element. These variations in resistance are measured as a voltage
and used to calculate gas concentrations.
<Detecting element diagram>Metal oxide
semiconductor<Drive circuit>

Platinum coil
0.5 - 1.4 mm

Constant
current
source0.8 - 1.4 mm

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Detecting element
Semiconductor material⇒ Resistance changes⇒ Sensor output

Indicator

12. Appendix

12-1 Detection principle<Points to note when using the hot wire semiconductor type sensor>
In particular, note the following points when using the hot wire semiconductor type sensor:
1. The product may be subject to interference from gases or vapors other than the target gas.
Take care to avoid alarm activation due to interference. The product may also experience fluctuations
due to environmental changes (e.g., in temperature or humidity) at the location where it is installed.
2. The alarm setpoint should be set within the performance range of the device.
In facilities subject to the High Pressure Gas Safety Act, settings below the standard alarm setpoints
specified by Riken Keiki may result in false alarms.
3. The product is a safety device. It is not a control device.
Use the alarm contact outputs on the product with external alarm lamps or buzzers. Use the analog
signal output for indicators or external recorders. Riken Keiki rejects liability for malfunctions in cases inwhich this signal is used for any other controls.
4. The gas sensing parts in the gas detecting sensors of this product are metal-oxide porous sinteredalloys. The surface area of the gas sensing parts will shrink when silicone and sulfides attach to thesurface of the sintered bodies. This can impair sensitivity significantly.
For safety reasons, avoid using this product in environments containing even trace amounts of silicone
or sulfides.
5. Regular maintenance is essential, including periodic parts replacement and readjustments as describedin this operating manual. The product is a safety device. We recommend regular maintenance and gas
calibration every six months in accordance with regulations.

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12. Appendix

12-2 Terminology

12-2 Terminology
Term
Dust filter

vol%
ppm
ppb
%LEL
Calibration

Maintenance mode

Initialization

Zero suppression
Alarm delay time
INHIBITDefinition
Filter for removing dust
We recommend fitting an external dust filter if the product will be used in
dusty surroundings. Different filters are specified for different detection
target gases. Contact our sales department.
Indicates gas concentrations in units of parts per hundred by volume.
Indicates gas concentration in units of parts per million by volume.
Indicates gas concentrations in units of parts per billion by volume.
Unit in which the lower explosive limit (LEL) of the target combustible
gas is set to 100
Refers to an evaluation of the correlation between product readout
values, display values, and setting values with actual values using
calibration gas.
Mode for performing device maintenanceDuring product maintenance, the alarm contacts are cut off, and theexternal output signal outputs a signal indicating the product is inmaintenance mode. This enables the device to be isolated formaintenance.
During the few seconds after turning on the power, the readings are
unstable. This function cuts off alarm contacts during this time to prevent
errors. The external output outputs a signal indicating the product is ininitialization mode.
This function makes fluctuations in ambient conditions and interference
gas less noticeable.
This function temporarily suspends activation to prevent false alarms
caused by external noise.
This function temporarily stops gas detection functions during productmaintenance, etc. This is also called "point skip," which has the samefunction.

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Revision History
Issue

Revision details

Issue date

0First issue (PT2-3041)

12/20/2022

1

CE Declaration of Conformity

5/31/2024