PT2E-3520

Gas Detector with Signal Converter
SD-3 Series

Operating ManualContents

Contents
1.

2.

3.

4.

Product Overview ................................................................................................................................................. 4
1-1 Introduction .................................................................................................................................................. 4
1-2 Intended use and features .......................................................................................................................... 6
1-2-1 Models and Codes ........................................................................................................................... 6
1-2-2 Detection principles and detection target gases for individual models ........................................... 7
1-2-3 Product features ............................................................................................................................... 8
1-3 Usage zones and conditions ....................................................................................................................... 9
1-4 DANGER, WARNING, and NOTE............................................................................................................ 10
1-5 Method of confirmation for Standards and Explosion proof specification ................................................ 10
Important Safety Information .............................................................................................................................. 11
2-1 Danger information .................................................................................................................................... 11
2-2 Warning information .................................................................................................................................. 11
2-3 Caution information ................................................................................................................................... 12
2-4 Safety information...................................................................................................................................... 13
Product Configuration......................................................................................................................................... 30
3-1 Main unit and accessories......................................................................................................................... 30
3-1-1 Main unit (SD-3) ............................................................................................................................. 30
3-1-2 Main unit (SD-3SC) ........................................................................................................................ 31
3-1-3 Remote sensor head (GD-3) ......................................................................................................... 31
3-1-4 Standard accessories .................................................................................................................... 32
3-1-5 Optional accessories...................................................................................................................... 33
3-2 Part names and functions ......................................................................................................................... 36
3-3 Block diagrams .......................................................................................................................................... 37
Installation ........................................................................................................................................................... 39
4-1 Installation precautions.............................................................................................................................. 39
4-1-1 General installation information ..................................................................................................... 39
4-1-2 Restrictions regarding installation .................................................................................................. 40
4-2 System design precautions ....................................................................................................................... 44
4-2-1 Using a stable power supply.......................................................................................................... 44
4-2-2 Lightning strike protective measures ............................................................................................. 44
4-3 Providing maintenance space ................................................................................................................... 45
4-4 Main unit installation .................................................................................................................................. 47
4-4-1 Vertical pole mounting.................................................................................................................... 47
4-4-2 Wall mounting................................................................................................................................. 48
4-4-3 Attaching protective cover.............................................................................................................. 49
4-4-4 Attaching sunshade cover ............................................................................................................. 51
4-5 Remote sensor head (GD-3) installation .................................................................................................. 53
4-5-1 Wall mounting................................................................................................................................. 53
4-5-2 Duct mounting ................................................................................................................................ 53
4-6 Connecting the grounding terminal ........................................................................................................... 55
4-7 Connecting the power and signal cables .................................................................................................. 56
4-7-1 Main unit cable and device connectors ......................................................................................... 56
4-7-2 Connecting the power and signal cables to the main unit ............................................................ 58
4-7-3 Connecting the power and signal cables to the remote sensor head (GD-3) ....................................... 61
4-7-4 Connecting the main unit (SD-3SC) and remote sensor head (GD-3)......................................... 64
4-7-5 Connecting cables to the terminal plate ........................................................................................ 69
4-8 Mounting the sensor .................................................................................................................................. 72
4-9 Alarm relay setting (option) ....................................................................................................................... 73
4-10 Mounting the splash guard...................................................................................................................... 76

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Contents

5.

6.

7.

8.

Usage Instructions .............................................................................................................................................. 78
5-1 Preparations for startup ............................................................................................................................. 78
5-2 Startup ....................................................................................................................................................... 79
5-3 Basic operation flow .................................................................................................................................. 81
5-4 Operating procedure ................................................................................................................................. 82
5-5 User mode ................................................................................................................................................. 83
5-5-1 User mode setting items ................................................................................................................ 83
5-5-2 Switching to user mode ................................................................................................................. 84
5-6 Performing zero calibration ....................................................................................................................... 85
5-7 Checking settings ...................................................................................................................................... 87
5-7-1 Checking alarm setpoints .............................................................................................................. 87
5-8 Shutting down ............................................................................................................................................ 89
Storage, Relocation, and Disposal..................................................................................................................... 90
6-1 Procedures for storage or when not in use for extended periods ............................................................ 90
6-2 Procedures for relocation or reuse............................................................................................................ 92
6-3 Product disposal ........................................................................................................................................ 92
Troubleshooting .................................................................................................................................................. 93
7-1 Product abnormalities................................................................................................................................ 93
7-2 Reading abnormalities............................................................................................................................... 94
Product Specifications ........................................................................................................................................ 96
8-1 Detection target gases for individual detection principles ........................................................................ 96
8-1-1 Non-dispersive infrared absorption type (Infrared type)................................................................ 96
8-1-2 New ceramic type .......................................................................................................................... 98
8-1-3 Semiconductor type ....................................................................................................................... 99
8-1-4 Hot-wire semiconductor type ....................................................................................................... 101
8-1-5 Electrochemical type .................................................................................................................... 103
Product warranty .............................................................................................................................................. 104
Sensor warranty ............................................................................................................................................. 104
Revision History................................................................................................................................................ 105

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1. Product Overview

1-1 Introduction

1

Product Overview
1-1 Introduction
Thank you for purchasing the SD-3 Gas Detector with Signal Converter (“product” hereinafter).
This operating manual describes the outline, installation, and operation of this product. It provides information
essential to 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.
For more information on product maintenance and setting changes, refer to the Technical Manual available fordownload from our website.
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.
Be sure to read the warranty policy at the end of this document.
Before using the product, please confirm that the model of the product you purchased matches the model of the
product covered by this operating manual.

<Models covered by this operating manual>

Main unit

Main unit

Remotesensor head

Diffusion typeSD-3RI
SD-3NC
SD-3GH
SD-3GHS
SD-3SP
SD-3EC
SD-3ECS
SD-3ECB
SD-3SCGD-3RI
GD-3NCGD-3GH
GD-3GHS
GD-3SP
GD-3ECGD-3ECS
GD-3ECB

Suction typeSD-3DRI
SD-3DNC
SD-3DGH
SD-3DGHS
SD-3DSP
SD-3DEC
SD-3DECS
SD-3DECB

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1. Product Overview

1-1 Introduction<This operating manual>In this operating manual, where descriptions differ according to the detection principle, these are indicated by
the following icons:
Non-dispersive infrared absorption type(infrared type)

RI

New ceramic typeNC

Semiconductor typeGH

Hot-wire semiconductor type

SP

Electrochemical typeEC

Operating procedures and specifications for which no icons appear apply to all detection principles.
The display examples provided in this operating manual apply when the detection target gas is combustible(display units: %LEL).

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1. Product Overview

1-2 Intended use and features

1-2 Intended use and features
The product is a fixed explosion-proof device for continuous monitoring of combustible gases, toxic gases, andoxygen in the air.
An alarm is triggered if combustible gases, toxic gases, or oxygen exceeding preset concentrations aredetected in the air.
The detection results are not intended to assure life or safety.

1-2-1
SD-3

Models and Codes
①

②

（ ③

1

0

0

⑦

⑧ ）

[Remote type: Main unit (SD-3SC) + Remote sensor unit (GD-3)]
SD-3SC ( ③
1
0
0
⑦
⑧)
GD-3 ①②①②

Diffusion type/suction type selection
Blank Diffusion typeD
Suction type (introduced via external unit)
Sensor type selection
RI
Infrared typeNC
New ceramic typeGH
Semiconductor type
Semiconductor type (selectable for CS2
GHS
only)
SP

⑥

⑦

Hot-wire semiconductor type

Electrochemical type (selectable for
CO/O2 only)
Electrochemical type (selectable for H2S
ECS
only)
Electrochemical type (selectable for
ECB
gases other than CO/O2/H2)
Cable connectors
0Connector 1 + Connector 2 [Standard]
Connector 1 + Connector 2+ Connector
1
4 + Connector 5
Explosion-proof
1
ATEX/IECEx/UKEX [Standard]
2
34
Functional safety0None [Standard]
1
EC

③

④

⑤

⑧

Performance certification
0
None [Standard]
123
Range setting*0Single range [Standard]
Double range +4-16 (selectable1with NC only)
Double range + L4-20 (selectable2
with NC only)
Double range + H4-20 (selectable3
with NC only)
Output type selection
0

4-20 mA + HART [Standard]

124-20 mA + HART + contact (3c)-

*HART communication is unavailable when double range(optional) is selected.

Connector
3*Not used

Connector
2

Connector
4Standard

Optional

Connector
1

Connector
5Standard

Optional
Example: Cable connectors

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1. Product Overview

1-2-2

1-2 Intended use and features

Detection principles and detection target gases for individual models

The product is available in the following models, depending on the specific detection method and detection
principle.
Check the specifications before use to confirm that correct gases will be detected in accordance with theintended purpose.
<List of detection target gases by model>
Main unit
model

Detection
methodDetection target gas
Detection principle

Combustible gas

Toxic
gas

〇

SD-3RI

Non-dispersive infraredabsorption type(infrared type)〇

SD-3NCNew ceramic type〇SD-3GH

Semiconductor type〇SD-3GHS

Diffusion

Semiconductor type

OxygenRemarks〇
CS2 (carbon disulfide) only〇

SD-3SP

Hot-wire semiconductor
type

SD-3ECElectrochemical type〇

SD-3ECS

Electrochemical type〇

H2S (hydrogen sulfide)only

SD-3ECBElectrochemical type〇

With EC barrier*SD-3DRI

Non-dispersive infraredabsorption type(infrared type)〇SD-3DNC

New ceramic type〇SD-3DGH

Semiconductor type〇SD-3DGHS

Suction〇Semiconductor type

〇
〇

〇

〇
CS2 (carbon disulfide) only〇

SD-3DSP

Hot-wire semiconductor
type

SD-3DEC

Electrochemical type〇SD-3DECSElectrochemical type〇

H2S (hydrogen sulfide)only

SD-3DECB

Electrochemical type〇

With EC barrier*〇*Differs depending on detection target gas.

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1. Product Overview

1-2 Intended use and features<List of detection target gases by model (remote sensor type)>
Main unit model

SD-3SC

Remotesensor headmodel

Detection
methodDetection principle

Detection target gas
Combus- Toxic
Oxygentible gas
gas

GD-3RI

Non-dispersive infraredabsorption type(infrared type)〇

GD-3NCNew ceramic type〇

GD-3GH

Semiconductor type〇

GD-3GHS

Semiconductor type

Diffusion

Remarks〇〇
CS2 (carbon disulfide)only〇

GD-3SP

Hot-wire semiconductor
type

GD-3ECElectrochemical type〇

GD-3ECS

Electrochemical type〇

H2S (hydrogen sulfide)
only

GD-3ECBElectrochemical type〇

With EC barrier*〇〇〇*Differs depending on detection target gas.

<Sensor models and detection principles>
Sensor model

Detection principle

IRF

Infrared typeNCF

New ceramic type

SGF

Semiconductor type

SHF

Hot-wire semiconductor type

ESF

Electrochemical type1-2-3

Product features<Standard specifications> The product is constructed with a stainless steel housing suitable for both indoors and outdoors use.
 Requires a 24 V DC (DC 18 V to 30 V) power supply.
 The gas concentration, status, and command selection menu are displayed using seven-segment LEDs.
 The concentration of the gas detected is converted to a 4 - 20 mA analog output (NAMUR NE43 compliant)or a digital HART output signal.
 It can be connected to a Riken Keiki monitoring system or programmable logic controller (PLC) via a ceiling
fitting or approved cable gland.

<Optional specifications> The product can be operated as a standalone unit by setting an alarm relay. Using the product as astandalone unit allows control of devices without the need for a central controller.*1*1: Using the product as a standalone unit requires additional alarm signal settings.

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1. Product Overview

1-3 Usage zones and conditions

1-3 Usage zones and conditions
The product is approved for use in areas where gases classified in explosive gas groups IIA, IIB, or IIC may bepresent. This refers to use limited to hazardous zones categorized as Zone 1 or Zone 2 within the productoperating temperature range.

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1. Product Overview

1-4 DANGER, WARNING, and NOTE

1-4 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.

1-5 Method of confirmation for Standards and Explosion
proof specification
This instrument has some specification depends on standard and explosion proof certificate. Please confirm thedetector specification before using. Please refer Declaration of Conformity that is at the end of this manual if you
have CE/UKCA marking type. You can confirm instrument specification to see name plate as follows.

< SD-3 >ATEX/IECEx/UKEX
CE/UKCA marking type name plate

CE marking< GD-3 >UKCA marking

10 / 105

2. Important Safety Information

2-1 Danger information

2

Important Safety
Information
2-1 Danger information
DANGER
 Do not open the cover while the power is turned on. When opening the cover, use a portable gas
detector or other similar device to confirm that there is no gas present in the vicinity.
 Do not attempt to repair the product.
 Do not attempt to repair or replace the explosion-proof bonding surface. If you observe scratches, cracks,
or deformation on the housing or explosion-proof bonding surface, stop using the product immediately
and contact Riken Keiki promptly.

2-2 Warning information
WARNING Before turning on the power for the product, be sure to confirm that the power source meets the specified
voltage requirements.
Using power supplies other than the stipulated voltage will damage the product. Do not use unstable
power supplies. Doing so may result in malfunctions.
 Do not disconnect the protective grounding wire or terminal.
 Before operating the product, check the protective functions for defects.
Do not operate the product if you suspect any problems with the protective grounding or other protectivefunctions.
 Connect to a protective ground before connecting to external control circuits.
 Before adjusting zero for the surrounding atmosphere, confirm that the surrounding atmosphere contains
clean air.
The presence of interference gases will prevent proper air calibration. The presence of miscellaneous
gases is also extremely dangerous because the product may not detect actual gas leaks correctly.
 A gas alarm indicates the presence of extreme danger. The user must take appropriate action after taking
suitable steps to ensure safety.
 Do not immerse the product in organic solvents for extended periods. The flame arrester components are
made of polyphenylene sulfide (PPS) resin.

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2. Important Safety Information

2-3 Caution information

2-3 Caution information
CAUTION The product operation may be affected by radio waves emitted from walkie-talkies or other radiotransmitters used near the product or its cables. Position walkie-talkies or other similar devices so thatthey do not affect the product operation.
 Wait at least 10 seconds before turning the power back on again after turning off. The product may not
function correctly if the power is turned back on immediately.
 The product is not a control device. Never use the product output to control other devices.
 Do not disassemble or alter the product. Product performance cannot be guaranteed if the product isdisassembled or modified.
 Do not alter settings unnecessarily unless you are fully aware of the consequences. Doing so may resultin improper alarm function. Avoid performing any operations not described in this operating manual.
 The product is a safety device. Be sure to maintain the product at regular intervals to ensure safety.
Continuing to use the product without adequate maintenance will result in sensor sensitivity degradationand prevent proper gas detection.

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2. Important Safety Information

2-4 Safety information

2-4 Safety information<Product overview> The products have an explosion-proof construction.
 Sensors are divided into three different types, depending on the corresponding detection principles. The
detection methods are divided into the diffusion type and suction type. Suction-type sensors should be usedwith a suction cap fitted.
 The product is a fixed, continuous monitoring detector. It can be connected to a gas monitoring control unit,
recorder, or programmable control unit to output the measured gas readings as a 4 - 20 mA signal or HART
signal.
 The following three sets of output specifications are available for this product:
・ No alarm relay, no digital communication
・ 3 alarm relays (contact output) (alarm relays operate in conjunction with gas alarms and faults), no
digital signal
・ No alarm relay, digital communication (RS-485 output) The electrochemical sensor is made into an explosion-proof construction by using an EC barrier.

<Detection principles and models> The models corresponding to the individual detection principles are as follows. The models are classified bydetection principle and detection method.
Detection principle (Detection method: Diffusion type)

Model

Optical sensor

Non-dispersive infrared absorption type (infraredtype)

SD-3RI

Solid state sensor

Semiconductor typeSD-3GH
SD-3GHSElectrochemical sensor

New ceramic type

SD-3NC

Hot-wire semiconductor type

SD-3SPElectrochemical type

SD-3EC
SD-3ECS
SD-3ECB

Detection principle (Detection method: Suction type)

Model

Optical sensor

Non-dispersive infrared absorption type (infraredtype)

SD-3DRI

Solid state sensor

Semiconductor typeSD-3DGH
SD-3DGHS

Electrochemical sensor

New ceramic typeSD-3DNC

Hot-wire semiconductor typeSD-3DSPElectrochemical typeSD-3DEC
SD-3DECS
SD-3DECB

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2. Important Safety Information

2-4 Safety information

 The SD-3SC is used with a remote sensor head (GD-3) from among the following models:Model
Detection principle (Detection method: Diffusion type)
GD-3(Remote sensor head)
Optical sensor
Non-dispersive infrared absorption
GD-3RI
type (infrared type)
Solid state sensor
Semiconductor type
GD-3GH
GD-3GHSNew ceramic type
GD-3NC
Hot-wire semiconductor type
GD-3SPElectrochemical sensor Electrochemical type
GD-3ECGD-3ECS
GD-3ECB

SD-3

SD-3SCWARNING The SD-3EC and GD-3EC models are subdivided by the type of explosion-proof construction of theflame arrester fitted to the sensor and whether they include an EC barrier.
The expected explosion-proof performance cannot be ensured if the incorrect flame arrestor is used. Do
not replace with a different flame arrester.
 The SD-3GH and GD-3GH models are subdivided by the type of explosion-proof construction of theflame arrester fitted to the sensor.
The expected explosion-proof performance cannot be ensured if the incorrect flame arrestor is used. Do
not replace with a different flame arrester.

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2. Important Safety Information

2-4 Safety information<Explosion-proof performance data>
The range of ambient temperatures in which explosion-proof performance can be maintained will differ dependingon whether the optional lightning arrester is fitted.
Refer to the following performance data for each model:<Without lightning arrester>
Explosionproof
construction

Group

Category

Explosion-proof
class

EPL

Ambient temperature*1

d

II

2G

Ex db IIC T6/T5

Gb-50 °C ≤ Ta ≤ +60 °C /+70 °C

d

II

2G

Ex db IIC T5/T4

Gb-50 °C ≤ Ta ≤ +44 °C /+70 °C

d

II

2G

Ex db IIC T6/T4

Gb-50 °C ≤ Ta ≤ +47 °C /+70 °C

d

II

2G

Ex db IIC T5/T4

Gb-50 °C ≤ Ta ≤ +44 °C /+70 °C

d

II

2G

Ex db IIC T5/T4

Gb-50 °C ≤ Ta ≤ +55 °C /+70 °C

d

II

2G

Ex db IIC T4

Gb-50 °C ≤ Ta ≤ +70 °C

d

II

2G

Ex db IIC T4

Gb-50 °C ≤ Ta ≤ +70 °C

d+i

II

2G

Ex db ia IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

SD-3SC*2

d

II

2G

Ex db IIC T6/T5/T4

Gb-50 °C ≤ Ta ≤ +47 °C /+55 °C+70 °C

SD-3SC*3

d

II

2G

Ex db IIC T5/T4

Gb-50 °C ≤ Ta ≤ +44 °C /+70 °C

SD-3SC*4

d

II

2G

Ex db IIC T6/T5

Gb-50 °C ≤ Ta ≤ +60 °C /+70 °C

SD-3SC*5

d

II

2G

Ex db IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

Model

SD-3RI
SD-3DRI
GD-3RI
SD-3GH
SD-3DGH
GD-3GH
SD-3GHS
SD-3DGHS
GD-3GHS
SD-3NC
SD-3DNC
GD-3NC
SD-3SP
SD-3DSP
GD-3SP
SD-3EC
SD-3DEC
GD-3EC
SD-3ECS
SD-3DECS
GD-3ECS
SD-3ECB
SD-3DECB
GD-3ECB*1: The ambient temperature refers to temperatures in the range within which explosion-proof performance can be
maintained. It does not imply the temperature range within which the required product performance may beachieved. For information on the operating temperature range, refer to ‘8-1 Detection target gases for individual
deterction principles’.
*2: When used in combination with GD-3GHS, GD-3SP, GD-3EC, and GD-3ECS*3: When used in combination with GD-3GH and GD-3NC*4: When used with the GD-3RI*5: When used in combination with GF-3ECB

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2. Important Safety Information

2-4 Safety information<With lightning arrester>
Explosionproof
construction

Group

Category

Explosion-proof
class

EPL

Ambient temperature*1

d

II

2G

Ex db IIC T6/T5

Gb-40 °C ≤ Ta ≤ +60 °C/+70 °C

d

II

2G

Ex db IIC T5/T4

Gb-40 °C ≤ Ta ≤ +44 °C /+70°C

d

II

2G

Ex db IIC T6/T4

Gb-40 °C ≤ Ta ≤ +47 °C /+70°C

d

II

2G

Ex db IIC T5/T4

Gb-40 °C ≤ Ta ≤ +44 °C /+70 °C

d

II

2G

Ex db IIC T5/T4

Gb-40 °C ≤ Ta ≤ +55 °C /+70 °C

d

II

2G

Ex db IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

d

II

2G

Ex db IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

d+i

II

2G

Ex db ia IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

SD-3SC*2

d

II

2G

Ex db IIC
T6/T5/T4Gb-40 °C ≤ Ta ≤ +47 °C /+55 °C+70 °C

SD-3SC*3

d

II

2G

Ex db IIC T5/T4

Gb-40 °C ≤ Ta ≤ +44 °C /+70 °C

SD-3SC*4

d

II

2G

Ex db IIC T6/T5

Gb-40 °C ≤ Ta ≤ +60 °C /+70 °C

SD-3SC*5

d

II

2G

Ex db IIC T4

Gb-40 °C ≤ Ta ≤ +70 °C

Model

SD-3RI
SD-3DRI
GD-3RI
SD-3GH
SD-3DGH
GD-3GH
SD-3GHS
SD-3DGHS
GD-3GHS
SD-3NC
SD-3DNC
GD-3NC
SD-3SP
SD-3DSP
GD-3SP
SD-3EC
SD-3DEC
GD-3EC
SD-3ECS
SD-3DECS
GD-3ECS
SD-3ECB
SD-3DECB
GD-3ECB*1: The ambient temperature refers to temperatures in the range within which explosion-proof performance can be
maintained. It does not imply the temperature range within which the required product performance may beachieved. For information on the operating temperature range, refer to ‘8-1 Detection target gases for individual
deterction principles’.
*2: When used in combination with GD-3GHS, GD-3SP, GD-3EC, and GD-3ECS*3: When used in combination with GD-3GH and GD-3NC*4: When used with the GD-3RI*5: When used in combination with GF-3ECB

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2. Important Safety Information

2-4 Safety information<Electrical data>
Option (select one)
Model

Supply voltage

Powerconsumption

Signal output

No alarm relay/
No digitalcommunication

SD-3RI
SD-3DRI
GD-3RI
SD-3GH
SD-3DGH
GD-3GH
SD-3GHS
SD-3DGHS
GD-3GHS
SD-3NC
SD-3DNC
GD-3NC
SD-3SP
SD-3DSP
GD-3SP
SD-3EC
SD-3DEC
GD-3EC
SD-3ECS
SD-3DECS
GD-3ECS
SD-3ECB
SD-3DECB
GD-3ECB
SD-3SC

Alarm relay(contact output)/

DigitalResistance load

communication

only

24 V DC(18 V - 30 V
DC Max)

3.8 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

1.2 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

4.5 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

2 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

4.5 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

2 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

4.5 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

2 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

3.5 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

1 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

2.8 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

1 W Max

―

―

―

―

24 V DC(18 V - 30 V
DC Max)

2.8 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output

1 W Max――――
RS-485 output

24 V DC(18 V - 30 V
DC Max)24 V DC(18 V - 30 V
DC Max)

3.1 W Max0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

1 W Max

―

―

―

―

5 W Max

0 - 22 mA + HART―

30 V DC, 1 A
250 V AC, 2 A

RS-485 output<Certificate numbers>
 IECEx PRE 20.0064 X
 Presafe 20 ATEX 69725 X
 DNV 22 UKEX 25924X* The “X” at the end of the certificate number indicates the following special operating conditions:・ The flameproof joints are not intended to be repaired.
・ Regarding ATEX specification, the measuring function according to Annex II paragraph 1.5.5 of the Directive
is not covered by this EU-type examination.
It shall comply with the requirements from the relevant European harmonized standards which provide
guidance on the performance of gas detection equipment and safety devices.
・ The measuring function according to schedule 1, paragraph 24 of the Regulation is not covered in this UKtype examination. It shall comply with the requirements from the relevant UK Designated Standards which
provide guidance on the performance of gas detection equipment.
・ The Equipment with glass window plate must only be placed in areas with low risk of mechanical danger(ref clause 26.4.2 in EN 60079-0).
・ The manufacturer’s instructions provides guidance for the user to minimize the risk from electrostatic
discharge. Maximum capacitance of 6 nF can occur.
・ If attached to a flameproof enclosure the surge protectors shall be provided with a high strength locking
compound on the mounting thread.
・ Refer to manual for ambient temperature.
17 / 105

2. Important Safety Information

2-4 Safety information

・ The measuring function of the EUT is not covered by this type examination. It shall comply with therequirements from the relevant harmonized standards which provide guidance on the performance of gas
detection equipment and safety devices.
・ The client should not try to replace the batteries.

<Applicable standards>
 IEC 60079-0:2017
 IEC 60079-1:2014
 IEC 60079-11:2011
 EN IEC 60079-0:2018
 EN 60079-1:2014
 EN 60079-11:2012
 BS EN IEC 60079-0:2018
 BS EN 60079-1:2014
 BS EN 60079-11:2012
<Operating manual no.> PT2-287

2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744, Japan
Phone:+81-3-3966-1113
Fax:+81-3-3558-9110
Email:
intdept@rikenkeiki.co.jp
Website:https://www.rikenkeiki.co.jp

18 / 105

2. Important Safety Information

2-4 Safety information<System configuration diagrams>

Installation diagram
Hazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3)
Display
POW(+)COM(−)
Sig(+)
Sig(−)

Signal cable

POW(+)COM(−)
Sig(+)
Sig(−)

Installation diagram
Hazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3)
Display
POW(+)COM(−)
Sig(+)
Sig(−)

RLY

Signal cable

Signal cable

19 / 105

POW(+)COM(−)
Sig(+)
Sig(−)RLY

2. Important Safety Information

2-4 Safety information

Installation diagram
Hazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3 (RS-485))
Display
POW(+)COM(−)
Sig(+)
Sig(−)

Signal cable

RS-485Signal cable

POW(+)COM(−)
Sig(+)
Sig(−)

RS-485

Installation diagram
Hazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3SC)
Display

Remote sensor head
(GD-3)
POW(+)COM(−)
RS-485(Y)RS-485(Z)Signalcable

POW(+)COM(−)
Sig(+)
Sig(−)

Signal cable

POW(+)COM(−)
RS-485(Y)RS-485(Z)20 / 105

POW(+)COM(−)
Sig(+)
Sig(−)

2. Important Safety Information

2-4 Safety information

Installation
diagramHazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3SC)
Display

Remote sensor head
(GD-3)
POW(+)COM(−)
RS-485(Y)RS-485(Z)Signalcable

POW(+)COM(−)
Sig(+)
Sig(−)

Signal cable

POW(+)RLY
COM(−)
RS-485(Y)RS-485(Z)Signal cable

POW(+)COM(−)
Sig(+)
Sig(−)

RLY

Installation diagram
Hazardous area
(Zone 1)Non-hazardousarea

Gas detector (SD-3SC)
Display
POW(+)COM(−)
Sig(+)
Sig(−)

Signal cable

Remote sensor head
(GD-3)
POW(+)COM(−)
RS-485(Y)RS-485(Z)Signalcable

RS-485
POW(+)COM(−)
RS-485(Y)RS-485(Z)POW(+)COM(−)
Sig(+)
Sig(−)

RS-485Signal cable

21 / 105

2. Important Safety Information

2-4 Safety information

CAUTION Install the product in accordance with the required installation conditions.
 Do not disassemble, modify, or alter the product.
 Contact Riken Keiki to request readjustment or parts replacement including calibration.
 Use cable lugs for grounding wire and bonding conductor connections. Make sure the bonding
conductors are not loose or twisted.
 Do not open the cover in locations where explosive gas may be present.
 The maximum pressure inside the gas channels and sensor is 10.13 kPa (gauge pressure).
 Be sure to connect the grounding terminal before turning on the power to the product.
 Make sure the grounding is Class D equivalent (grounding resistance less than 100 Ω).
 Use crimped terminals to connect the grounding wire to the grounding terminal inside the unit. Use acable with a cross section area of at least 4 mm2 to connect to the external grounding terminal.
 Use approved cable glands when installing.
 If the product is installed in a location where the ambient temperature exceeds 65 °C, use cables
designed for use at temperatures at least 5 °C above the maximum ambient temperature.
 Do not subject the window in the cover to strong forces or impact. Doing so may result in damage andimpaired explosion-proof performance. (The low risk of mechanical hazards has been confirmed in
testing [2 joules].) Do not use more than one adapter per connector.

CAUTION
With suction type
 Use with a flow rate of at least 0.4 L/min and not exceeding 1.5 L/min.

22 / 105

2. Important Safety Information

2-4 Safety information<Connector screw thread types and sizes (SD-3/SD-3SC)>
Connector 3

Connector 2Connector 4

Connector 5

Connector 1

Connector 6<Standard>
Connector 1

Connector 2Connector 3

Connector 4

Connector 5

Connector 6

M25 × 1.5

M25 × 1.5―――

M25 × 1.5

 “―” indicates no connector is available.
 Connectors 1, 2, and 6 can be used as cable entry ports. Use Connector 6 if the main unit (SD-3SC) is
connected to the remote sensor head (GD-3) with a cable. Use approved cable glands when connecting the
remote sensor head (GD-3).
 Blank off unused connectors with blanking plugs.
 For more information on using individual connectors, refer to ‘4-7 Cable connection’.
<Optional>
Connectors 4 and 5 are available with optional screw threads, as follows:
Connector 1

Connector 2Connector 3

Connector 4

Connector 5

Connector 6

M25 × 1.5

M25 × 1.5―

M25 × 1.5

M25 × 1.5

M25 × 1.5

 “―” indicates no connector is available.
 Connectors 1, 2, 4, and 6 can be used as cable entry ports. Use Connector 6 if the main unit (SD-3SC) is
connected to the remote sensor head (GD-3) with a cable. Use approved cable glands when connecting the
remote sensor head (GD-3).
 Up to two external cable connectors can be used at the same time. (Excluding the remote sensor head
(GD-3) connector cable) Connector 2 or 4 can be used to connect the optional lighting arrester using the optional adapter (to convert
M25 × 1.5 screw thread to 1/2 NPT screw thread).
 Connector 5 is used for HART communication with an optional HART modem connector. Do not insert
external cables or connect a lightning arrester. Blank off with a blanking plug if you do not use HART
communication.
 Blank off unused connectors with blanking plugs.
 For more information on using the individual connectors, refer to ‘4-7 Cable connection’.
23 / 105

2. Important Safety Information

2-4 Safety information<Components that can be connected (SD-3/SD-3SC)>
The following components can be connected to the main unit (SD-3/SD-3SC):
Connector Connector Connector Connector Connector Connector
1
2
3
4
5
6
Sensor assembly

×

×

×

×

×

〇

EC barrier

×

×

×

×

×

〇

Approved cable gland

〇

〇

×

〇

×

〇

M25 plug

〇

〇

×

〇

〇

×

Adapter(M25 ⇔ 1/2NPT)

〇

〇

×

〇

×

〇

Adapter(M25 ⇔ 3/4NPT)

〇

〇

×

〇

×

〇

Adapter(M25 ⇔ M20)

〇

〇

×

〇

×

〇

Lightning arrester

×

〇

×

〇

×

×

〇: Can be connected
×: Cannot be connected

NOTE
 Connect only components that are compatible with the individual connectors on the main unit (SD-3/SD3SC).
 Tighten M25 plugs and adapters to a torque of at least 30 Nm.
 Secure a minimum thread engagement of five threads.

<Lightning arrester details>
Manufacturer
Name/No.
Part
Explosion-proof
performance
No. and issue
Certification
Nos.

Rating
Installation

Applicable standards
Voltage/current
Temperature*
Attachment screw

Eaton Electric Limited
TP48 or TP32 series surge protector
II 2G Ex db IIC T6 Gb
IECEx BAS 15.0056X Issue 1, Baseefa 04 ATEX 0053X
EN 60079-0:2012+A11:2013
EN 60079-1:2014
IEC 60079-0:2011 Edition 6.0
IEC 60079-1:2014 Edition 7.0
48 V DC-40 - +70 °C
1/2NPT*The minimum ambient temperature for the SD-3/GD-3 when using a surge protector is -40 °C.

24 / 105

2. Important Safety Information

2-4 Safety information

The “X” at the end of the certificate number indicates the following special operating conditions:Certificate numbers

IECEx BAS 15.0056X
Baseefa 04 ATEX 0053X“X” specific operating conditions

Judgment

Use terminals suitable for the operating conditions or use
appropriate termination within the bonds to protect against
mechanical damage—for example, when pulling
connector cables.

Conforms asassembly.

These devices are not equipped with grounding or
external connectors to junction conductors. The user is
responsible for attaching and ensuring adequate
grounding.

Conforms asassembly.

This device is also provided as an “Ex i” version andfeatures markings for both. The user is responsible fordetermining explosion-proof performance.

Not applicable

When attaching to a flame-proof housing, apply highstrength thread-locking compound to the mounting screw
on the surge protector.

“X” marking

25 / 105

2. Important Safety Information

2-4 Safety information<Components that can be connected (GD-3)>

Connector 1

Connector 2Connector 3

The following components can be connected to the remote sensor head (GD-3):
Connector
1

Connector
2

Connector
3

Sensor assembly

×

×

〇

EC barrier

×

×

〇

Approved cable gland

〇

〇

×

M25 plug〇〇〇

Adapter(M25 ⇔ 1/2NPT)

〇

〇

〇

Adapter(M25 ⇔ 3/4NPT)

〇

〇

〇

Adapter(M25 ⇔ M20)

〇

〇

〇

〇: Can be connected
×: Cannot be connected

NOTE
 Connect only components that are compatible with the individual connectors on the remote sensor head
(GD-3).
 Tighten M25 plugs and adapters to a torque of at least 30 Nm.
 Secure a minimum thread engagement of five threads.

26 / 105

2. Important Safety Information

2-4 Safety information<Connection examples>
SD-3SCGD-3RI

SD-3SCGD-3ECB

27 / 105

2. Important Safety Information

2-4 Safety information<Exploded view><SD-3>

Container

Cover
Blanking plug

Blanking plug

Gas sensor
Sensor guard<GD-3>

Container

Cover
Blanking plug

Gas sensor

Sensor guard

28 / 105

2. Important Safety Information

2-4 Safety information<Screw holes on rear of container (SD-3)>
Four screw holes are located on the rear of the main unit container.
• Screw size: M5• Pitch: 0.8• Screw depth: 5• Maximum allowable length of male screw:
Lmax = 4.2 mm + x(“x” is the intermediate part thickness.)

Screw holes on rear ofcontainer (four locations)<Screw holes on rear and underside of container (GD-3)>
There are four screw holes on the rear of the container and four screw holes on the underside.
• Screw size: M5• Pitch: 0.8• Screw depth: 5• Maximum allowable length of male screw:
Lmax = 4.2 mm + x(“x” is the intermediate part thickness.)<Container rear>
Screw holes on rear of container(four locations)<Container underside>

Screw holes on underside ofcontainer (four locations)

29 / 105

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 anything is missing, contact Riken Keiki.

3-1-1

Main unit (SD-3)<Diffusion type><Model without EC barrier><Model with EC barrier><Suction type><Model without EC barrier><Model with EC barrier>

30 / 105

3. Product Configuration

3-1 Main unit and accessories

3-1-2

Main unit (SD-3SC)

3-1-3

Remote sensor head (GD-3)<Diffusion type><Model without EC barrier><Model with EC barrier>

31 / 105

3. Product Configuration

3-1-4

3-1 Main unit and accessories

Standard accessories
Standard accessory

Quantity

Part No.

Variesdependingon quantity
ordered.

4286 9200 80

Key used to control the
product

Operating lever

×1

2594 0481 90

Tool used when connecting
cable to terminal plateHex key wrench(2 across flats)

Variesdependingon quantity
ordered.

1510 5020 40

Tool used for tightening M4
hex socket set screws

Control key

OperatingmanualDescription

×1

NOTE
 The quantity of control keys and hex key wrenches included will vary depending on the quantity of
product units ordered.
1 - 10 units:
×1
11 - 20 units:×2
21 - 50 units:
×3
51 or more units: ×4

CAUTION Use the control key provided to operate the product. The product may not respond properly to commands
if an object other than the supplied control key is used.
 The control key provided incorporates an extremely strong magnet. Holding the control key close to credit
cards, ID cards, or other magnetized products may corrupt data recorded on these objects.

32 / 105

3. Product Configuration

3-1-5

3-1 Main unit and accessories

Optional accessories
Optional accessory

Calibration adapter(for IRF sensor)

Calibration adapter(for combustible
gas sensor)

Calibration adapter(for ESF sensor)

Protective cover

Sunshade coverSplash guard(for IRF sensor)

33 / 105

Part No.

Description

4283 9011 00

SD-3RI calibration adapter<Material>
Body: PP
Nipple: Stainless steel/Teflon

4283 9012 70

SD-3NC/GH/GHS/SP
calibration adapter<Material>
Body: PP
Nipple: Stainless steel/Teflon

4283 9013 40

SD-3EC/ECS/ECB calibration
adapter<Material>
Body: PP
Nipple: Stainless steel/Teflon

4283 9019 80

Cover to protect the SD-3
main unit<Material>
SUS3164283 9015 90

Cover to suppress
temperature rises due to
direct sunlight or radiant heat
<Material>
SUS3164283 4136 1A

SD-3RI cover to protect
sensor from water and dust
The identification number “1”is engraved on the underside.
<Material>Resin3. Product Configuration

3-1 Main unit and accessories

Optional accessory

Part No.

Description

4283 4137 9A

SD-3NC/GH/GHS/SP cover toprotect sensor from water anddust
The identification number “2”is engraved on the underside.
<Material>
Resin

Splash guard(for ESF sensor)

4283 4139 3A

SD-3EC/ECS/ECB cover toprotect sensor from water anddust
The identification number “3”is engraved on the underside.
<Material>
Resin

Blanking plug

4283 9018 10

M25 × 1.5 blanking plug
<Material>
Equivalent to SUS316

4283 4081 70

Adapter to convert M25 × 1.5
screw thread to 1/2NPT screw
thread<Material>
Equivalent to SUS316

4283 4082 40

Adapter to convert M25 × 1.5
screw thread to 3/4NPT screw
thread<Material>
Equivalent to SUS316

4283 4132 20

Adapter to convert M25 × 1.5
screw thread to M20 × 1.5
screw thread<Material>
Equivalent to SUS316

4283 0030 20

Filter for removing trace
amounts of silicone from theair. This can extend sensor
life.*1

Splash guard(for combustible
gas sensor)

Adapter

Adapter

Adapter

Silicone removal
filter(SI-8)*3

34 / 105

3. Product Configuration

3-1 Main unit and accessories

Optional accessory

Part No.

Description

4283 0040 10

Filter for removing trace
amounts of silicone from theair. This can extend sensor
life.
The silicone removal
capability of this filter exceedsthat of the silicone removal
filter.*2
It can also be used to remove
interference gases. This canminimize interference effects
from gases other than thedetection target gas.

Duct mounting kit

4283 9014 10

Kit for installing a remotesensor head (GD-3) to a duct
<Material>
SUS316

HART modem
connector

2905 2439 10

Connector used whenconnecting a HART modem

Lightning arrester(3-wire connection)(TP48-3-N-NDI)

2032 0099 50

Device to limit momentary
surge voltages caused bylightning strikes

Lightning arrester(4-wire connection)(TP48-4-N-NDI)

2032 0116 40

Device to limit momentary
surge voltages caused bylightning strikes

Fuse2564 0125 10

Littelfuse’s fuse
(1.25 A, 100 V DC)

4283 9046 30

Bolt used for mounting themain unit to a pole (size: 50A(2B))<Material>
SUS304

Activated carbon
filter(CF-8304) *3

U bolt*1: Installing the silicone removal filter will limit the target gases that can be detected.
*2: The range of target gases that can be detected will be more limited than when the silicone removal filter is fitted.
*3 If you use a filter, we recommend fitting a splash guard.

35 / 105

3. Product Configuration

3-2 Part names and functions

3-2 Part names and functions＜SD-3＞<Display (same for both SD-3 and SD-3SC)>⑥ ⑦ ⑧ ⑨ ⑩

①

④

②

⑭
⑤

③

＜SD-3SC＞

⑪ ⑫ ⑬

No.
①

②
③

④
⑤
⑥
⑦
⑧
⑨
⑩
⑪

Name
MENU/ESC key

Function
Hold down this key in detection mode to switch to user mode.
In user mode and maintenance mode, this key is used to cancel a settingor return to the previous screen.
Hold down this key in user mode or maintenance mode to return todetection mode.
7-segment LED display Displays the gas concentration and other information.
Press in detection mode to display the ALM1 (first alarm) and ALM2
SET key(second alarm) alarm setpoints.
In user mode and maintenance mode, this key is used to confirm a value
or select a setting.
In user mode and maintenance mode, this key is used to select a setting▲ key
item and adjust (increase) a value.
In user mode, this key is used to switch menus or adjust (lower) a value.
▼ key
Press in detection mode to display the external output.
Power lamp. Lights up in green when the power is on.
Power lamp
The lamp flashes in green in user mode and maintenance mode.
(POWER)
ALM1 (first alarm) alarm lamp. Lights up in red when the ALM1 (first alarm)
Alarm lamp (ALM1)
alarm setpoint is reached.
IrDA communication port
Infrared port
ALM2 (second alarm) alarm lamp. Lights up in red when the ALM2
Alarm lamp (ALM2)(second alarm) alarm setpoint is reached.
Fault lamp. Lights up in yellow when an abnormality is detected in the product.
Fault lamp (FAULT)PPM lamp⑫%LEL lamp⑬% lamp⑭

SensorLights up in green when a ppm concentration range gas concentration isdisplayed.
Lights up (green) when a gas concentration within the %LEL concentration
range is displayed.
Lights up in green when a vol% concentration range gas concentration isdisplayed.
Incorporates a gas-detecting sensor.

36 / 105

3. Product Configuration

3-3 Block diagrams

3-3 Block diagrams
The block diagrams (electrical circuit diagrams) for the product are given below.

<SD-3>
Power supply unit
24 V DC

Display (LED)・ POWER・ ALM1
・ ALM2
・ FAULT・ PPM
・ %LEL
・ %Power supply voltage converter

External output
4 - 20 mA + HART

HART modem

Alarm contact output (option)
1. Gas alarm output (ALARM1)
2. Gas alarm output (ALARM2)
3. Fault output (FAULT)

Control
unit
CPU

Display
7-segment LED

Magnetic operation part・ MENU/ESC
・ SET
・ ▲
・ ▼

Contact operation
Normal measurement:
De-energized
Alarm state: EnergizedSensor37 / 105

3. Product Configuration

3-3 Block diagrams<SD-3SC>Power supply unit
24 V DC

Display (LED)・ POWER・ ALM1
・ ALM2
・ FAULT・ PPM
・ %LEL
・ %Power supply voltage converter

External output
4 - 20 mA + HART

HART modem

Alarm contact output (option)
1. Gas alarm output (ALARM1)
2. Gas alarm output (ALARM2)
3. Fault output (FAULT)

Control
unit
CPU

Display
7-segment LED

Magnetic operation part・ MENU/ESC
・ SET
・ ▲
・ ▼

Contact operation
Normal measurement:
De-energized
Alarm state: Energized

GD-3<GD-3>

SD-3SC
Controlunit
CPUPower supply voltage converter

38 / 105

Sensor4. Installation

4-1 Installation precautions

4

Installation
4-1 Installation precautions
Selecting an appropriate installation location is vital for system performance.
Be sure to observe the following precautions before installing.
Failure to comply with these precautions may result in failure of the product or improper function.

CAUTION The product is a precision device. Certain conditions at the location (environment) where the product isinstalled may prevent optimum performance. Check the environment at the installation location and takeall required precautionary measures depending on circumstances.
 Install the number of units needed at the appropriate locations to ensure that the product plays animportant role in safety and disaster prevention.
 Areas where gas is likely to leak or accumulate will differ depending on the gas type and individual work
areas. Thoroughly consider the installation locations and number of units to be installed before
installation.

4-1-1

General installation information

Observe the following precautions when installing the product: If the product is installed in a location where the ambient temperature exceeds 65 °C, use cables designed foruse at temperatures at least 5 °C above the maximum anticipated ambient temperature.
 The SD-3 and SD-3SC main units each have two M25 × 1.5 connectors for use when wiring in the field.
Connectors must always be blanked off with blanking plugs when not in use.
 The GD-3 has two M25 × 1.5 connectors for connecting the SD-3SC. The connector not in use must be
blanked off with a blanking plug at all times.
 Do not mount a sensor that uses a different detection principle from the model type.
 Use ferrules on the ends of stranded cables.
 Secondary circuits should be supplied from an insulated source. (Not suited to alarm relay contacts) If installing without using conduits, use cable glands that comply with the explosion-proof certification. In
addition, connect cable shielding to the main unit, cable glands, and indicators to increase immunity toelectromagnetic noise and other external factors.
 Select the cable, terminal plate, and other parts for wiring to alarm relays (optional) to suit the rated voltage,current, and environmental conditions.
In addition, carefully consider the following points when installing: All possible effects on the installation of the gas detector system
 Restrictions and regulations concerning the installation of the gas detector system
 Regulations concerning the operation, power supply, and signal cable connections for the gas detector
system Ambient environmental effects to which the gas detector system may be subject
 Specifics of the physical characteristics, environmental air movement and flows, and latent leaks of thedetection gas
 Accessibility for required maintenance and the shape of the accessories used

39 / 105

4. Installation

4-1-2

4-1 Installation precautions

Restrictions regarding installation<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 tovibration, impact, or risk of falling.

<Do not install in locations exposed to water, oil, or chemicals.>
Avoid installing in locations that pose the risk of splashing liquids such as water, oil, and chemicals. Deploy the
optional protective cover (main unit protection) and splash guard (sensor protection) if the product must be
installed in a location where it may be exposed to these factors.

<Do not install in locations where temperatures exceed the operating temperature
range.>For information on the product operating temperature range, refer to ‘8-1. Detection target gases for individual
detection principles’.
Install in a stable location where temperatures do not exceed the operating temperature range during use.

<Do not install in locations subject to direct sunlight or sudden temperature changes.>
Install away from locations subject to direct sunlight or radiant heat (infrared radiation from high temperature
bodies) and locations subject to sudden temperature changes. Failure to do so may expose the product totemperatures that exceed specified thresholds, internal condensation, or rapid temperature fluctuations the
product cannot handle.
Use of the optional sunshade cover is recommended when using the product in locations subject to direct
sunlight.

<Do not install in locations where maintenance is dangerous or not possible.>
The product requires periodic maintenance.
Do not install in the following or similar locations where maintenance is dangerous or not possible: Locations where systems must be stopped to allow 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, close to high-voltage cables<Do not install in improperly grounded system housings.>
When installing in a system housing, be sure to implement a Class D-equivalent ground connection.

<Do not install in the presence of miscellaneous gases.>
Do not install in locations where the following gases are present:
Sensor type
SGF
SHF
NCF

Gases affecting sensor sensitivity

Sensor-corroding gases

・ Organic silicone gas (e.g., D4 siloxane, D5 siloxane)
・ Sulfur gases (e.g., SOX, H2S)・ Corrosive gases (e.g., SOX,
NOX)・ Acid gases (e.g., HF, HCl)

IRF

None

ESF

None

None

<Precautions when installing in the presence of interference gases>
Take care when installing in locations where the following interference gases are present:
Sensor typeInterference gas
SGF
SHF

Hydrocarbons, alcohols, organic solvents, etc. other than the target gas

NCF

Hydrocarbons, alcohols, organic solvents, etc. other than the target gas

IRF

Combustible gas sensor: Hydrocarbons, alcohols, organic solvents, etc. other than thetarget gas
CO2 sensor: CO, N2O, NO, etc.

ESF

Differs depending on sensor. (e.g., H2 with CO sensor)

40 / 105

4. Installation

4-1 Installation precautions<Use the appropriate power supply and power cable.>
The product requires a 24 V DC (18 V - 30 V DC) power supply to operate. The power cable used should havea cross section of 1.308 mm2 (AWG16) or 2.082 mm2 (AWG14).
Use shielded 3-core cable.

<Install away from noise-emitting devices (main unit and cables).>
Install away from locations where high-frequency or high-voltage devices are present. Failure to do so may
result in electromagnetic interference.

<Use the appropriate impedance for the 4 - 20 mA signal output.>
The impedance for the 4 - 20 mA signal output must not exceed 600 Ω to ensure correct operation. This willvary depending on the voltage supplied to the product. The maximum and minimum impedance specified mustbe satisfied, based on factors such as product operating voltage and interface (HART).
<4 - 20 mA signal output impedance derating depending on supply voltage differences>

4 - 20 mA output load derating
700 Ω
600 Ω
500 Ω
400 Ω
300 Ω
200 Ω
100 Ω
0Ω
30 V 29 V 28 V 27 V 26 V 25 V 24 V 23 V 22 V 21 V 20 V 19 V 18 V 17 V 16 V 15 V

<4 - 20 mA signal output impedance range when using HART communication>
Devices equipped with a HART interface can be operated via HART communication or HART multidrop mode.
Operating mode

Signal impedance range for power supply voltage

Operation without HART communication

Max. 300 Ω at 18 V DC
Linear increase to max. 600 Ω at 23 V DC

Operation with HART communication(HART mode)

Min. 250 Ω in range 18 V - 30 V DC

HART multidrop operation

Max. 300 Ω at 18 V DC
Linear increase to max. 600 Ω at 23 V DC
250 Ω to 600 Ω in range 18 V - 30 V DC

<Use alarm contacts correctly.>
The alarm contacts on the product are used to transmit signals for operating external buzzers, alarm indicator
lamps, or revolving lights. Never use for controls on which human life depends or other mission critical controls(e.g., shutoff valve controls).
Check contact opening and closing periodically, including during regular maintenance. Contacts may not
function correctly under certain operating conditions if left inactive for extended periods.
The alarm contact specifications for the product apply under resistance load conditions. If inductive loads occur
at the alarm contacts, a counter-electromotive force will be generated at the contacts, leading to the following
potential problems:

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4. Installation

4-1 Installation precautions• Alarm relay contact welding, insulation failure, contact failure• Damage to electrical components due to high voltage inside the product• Malfunctions due to CPU runaway
If the product is used to operate loads, take the following measures to stabilize product operations and protect thealarm contacts:• Use an external relay (low voltage, not exceeding 100 V AC) to link the circuits (contact amplification). Add asurge absorber (SK1) appropriate for the rating to the external relay.
• Where necessary, add a surge absorber (SK2) on the load side of the external relay.
• Depending on the load conditions, it may be better to add the surge absorber to the contact side. Check load
behavior to determine the optimal location.
<SD-3>

Load

Coil

Alarm
contactPowersupplyPowersupplyExternal relay(low voltage relay)* SK1, SK2: Surge absorbers

DANGER Never use for controls on which human life depends or other mission critical controls (e.g., shutoff valve
controls).

WARNING Contacts may not function correctly if left inactive for extended periods. Check contact opening andclosing periodically.
 Contact faults may occur if exposed to organic gases or sulfidizing gases for extended periods.
 In principle, 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 is absolutely unavoidable, link the circuits using an external relay (contact
amplification). Since the external relay coil constitutes another inductive load, use a relay operating at low
voltage (under 100 V AC), and protect the product contacts with a suitable surge absorber (e.g., CR
circuit).
 Do not use in atmospheres where silicone is present.

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4. Installation

4-1 Installation precautions

CAUTION A de-energized b contact (break contact) may result in momentary opening in the event of an external
force or other physical impact. If a b contact is used as an alarm contact, implement measures to accountfor such momentary operations—for example, by adding a delay operation (of approximately one
second) to the signal on the b contact receiving side.

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4. Installation

4-2 System design precautions

4-2 System design precautions
Consider the following precautions when designing a system in which the product is used:

CAUTION An unstable power supply or noise may result in malfunctions or false alarms.
 Consider the details described in this section before designing a system that uses the product.

4-2-1

Using a stable power supply

The product’s external output and alarm contacts may activate as the system stabilizes when the power isturned on or right after an instantaneous power failure. If external output and alarm contacts activate due topower failures or other reason, use a UPS (uninterruptible power system) or take other appropriate measures.
The product should be powered using a power supply specified below.
Power supply voltage 24 V DC (18 V - 30 V DC): Main unit terminal voltage
Typical action:
Up to approx. 20 ms*1
Time allowed for
Use an external uninterruptible power
instantaneous
supply or similar system to guarantee
power failurescontinuous operation and functionality.
Do not use with power supplies
Typical action:
Miscellaneous
subject to very high power loads orWhere necessary, use a line filter or otherhigh frequency noise.
device. Keep the product away fromsources of noise.
*1: Restart the product when recovering after instantaneous power failures of 20 ms or more.

4-2-2

Lightning strike protective measures

In factories or plants where cabling is configured as follows, damage may result in the event of lightning strikes
due to the cables connected to the devices acting as a receiving antenna for the lightning: When cables are installed outdoors
 When cables are installed in the same duct as cables supplied from outside
In the event of lightning strikes, devices connected to the cables may be damaged by lightning energy.
Additionally, note that inductive lightning surges due to lightning strikes cannot be entirely prevented, even if
cables are installed in metal ducts or buried underground. While it is not possible to completely protect against
lightning disasters, the following protective measures are useful:<Lightning strike protective measures>
Implement appropriate measures based on environmental conditions and the importance of the facility.
A lightning arrester (cable protector) can be installed before the field devices and central processing equipment
as a safeguard against inductive lightning surges transmitted through the cables.
For information on how to use lightning arresters, please contact the manufacturer.

<Grounding>
Surge noise is caused by lightning strikes and other factors. Devices must be grounded to protect against thesenoise sources.

NOTE Lightning arresters contain circuitry to remove voltage surges that could damage field devices. Installing
lightning arresters may therefore cause signal attenuation.
Perform an operation check before installing a lightning arrester. Also note that lightning arresters cannot
remove all voltage surges.

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4. Installation

4-3 Providing maintenance space

4-3 Providing maintenance space
When mounting the product, allow space to open and close the covers during maintenance.

<Main unit (SD-3/SD-3SC)>
1200

300

*The diagram illustrates the SD-3. The maintenance space for the SD-3SC is identical.

<Remote sensor head (GD-3)>
1100

300

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4. Installation

4-3 Providing maintenance space

CAUTION
The product requires periodic maintenance.
Do not install in the following or similar locations where maintenance is dangerous or not possible: Locations such as within systems that 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, close to high-voltage cables

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4. Installation

4-4 Main unit installation

4-4 Main unit installation
4-4-1

Vertical pole mounting

Mount the main unit (SD-3/SD-3SC) to a vertical pole (size: 50A (2B)) using two U bolts.
1

Fit one U bolt around the vertical pole and through the upper slots on the main unit.

2

Secure the U bolt to the main unit with two washers, two spring washers, and two M10 nuts.

3

Fit the second U bolt around the vertical pole and through the lower slots on the main unit.

4

Secure the U bolt to the main unit with two washers, two spring washers, and two M10 nuts.
Vertical pole

U bolts

Upper slots

Lower slots*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

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4. Installation

4-4-2

4-4 Main unit installation

Wall mounting

Mount the main unit (SD-3/SD-3SC) to a wall.
1

Place the main unit against the wall surface and secure with four M10 double SEMS bolts.
Bolt positions

Bolt positions*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

CAUTION
The product requires periodic maintenance.
Do not install in the following or similar locations where maintenance is dangerous or not possible: Locations such as within systems that 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, close to high-voltage cables

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4. Installation

4-4-3

4-4 Main unit installation

Attaching protective coverAttach the protective cover to the main unit (SD-3/SD-3SC).

<Pole mounting (pole size: 50A (2B))>
1

Attach the chassis and mounting bracket to the main unit.
Secure with four M5  6 double SEMS bolts from behind,as shown in the diagram to the right.

ChassisMounting
bracket2

Fit one U bolt around the vertical pole and through theupper slots on the main unit. Secure with two washers, two
spring washers, and two M10 nuts.

3

Fit the second U bolt around the vertical pole and throughthe lower slots on the main unit. Secure with two washers,
two spring washers, and two M10 nuts.
U bolts

4
5

Attach the protective cover, aligning it with the two lugs at
the top of the chassis.

Lugs

Secure the protective cover in place by tightening theknurled screws on either side of the cover.

Protective cover

Knurled screw*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

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4. Installation

4-4 Main unit installation<Wall mounting>1

Secure the main unit and chassis with four M10 double
SEMS bolts.

ChassisLugs

2

Attach the protective cover, aligning it with the two lugs at
the top of the chassis.

3

Secure the protective cover in place by tightening theknurled screws on either side of the cover.

Protective cover

Knurled screw*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

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4. Installation

4-4-4

4-4 Main unit installation

Attaching sunshade coverAttach the sunshade cover to the main unit (SD-3/SD-3SC).

<Pole mounting (pole size: 50A (2B))>
1

2

Fit one U bolt around the vertical pole and through theupper slots on the main unit. Secure with the chassis, twowashers, two spring washers, and two M10 nuts.

ChassisU bolts

Fit the second U bolt around the vertical pole and throughthe lower slots on the main unit. Secure with two washers,
two spring washers, and two M10 nuts.

Vertical pole

3
4

Attach the sunshade cover, aligning it with the two lugs at
the top of the chassis.

Lugs

Secure the sunshade cover in place by tightening theknurled screws on either side of the cover.

Sunshade cover

Knurled screw*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

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4. Installation

4-4 Main unit installation<Wall mounting>1

Secure the main unit and chassis with four M10 double
SEMS bolts.

2

Attach the sunshade cover, aligning it with the two lugs at
the top of the chassis.

3

Secure the sunshade cover in place by tightening theknurled screws on either side of the cover.

Chassis

Lugs
Sunshade cover

Knurled screw*The diagram illustrates the SD-3. The mounting method for the SD-3SC is identical.

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4. Installation

4-5 Remote sensor head (GD-3) installation

4-5 Remote sensor head (GD-3) installation
4-5-1
1

Wall mounting

Place the remote sensor head (GD-3) against the wall surface and secure with two M6 double SEMS
bolts.

Bolt positions

4-5-2

Duct mounting

Attach the remote sensor head (GD-3) to a duct.
Attach to a duct using the duct mounting kit.
The duct mounting kit has the following dimensions:Remote sensor head (GD-3)

1

Cut out an opening in the top of the duct.
Refer to the diagram to the right for thedimensions of the opening.

Top of duct

100

180

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4. Installation

4-5 Remote sensor head (GD-3) installation2

Insert the remote sensor head (GD-3) into the duct
mounting kit and secure with four M5 bolts.
Connect a tube to the sensor on the remote sensor head
(GD-3) to enable calibration. The tube should protrude fromthe top of the duct mounting kit.

3

Insert the duct mounting kit into the opening in the duct.
Secure in place with six M6 bolts.

Duct mounting kit

300 or more

0NOTE
 When mounting the remote sensor head (GD-3) inside a duct,
make sure the sensor is not in contact with the duct inner wall.

Duct54 / 105

4. Installation

4-6 Connecting the grounding terminal

4-6 Connecting the grounding terminal
WARNING Be sure to ground the product before turning on the power.
 To ensure stable operation and safety, be sure to ground the product. Never connect grounding wires togas pipes.
 Make sure the grounding is Class D 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 the same locations as high frequency or high voltage devices or nearby.
Connect the grounding bolt to the local grounding terminal.
<Main unit (SD-3)>

Grounding bolt (M4)<Main unit (SD-3SC)>

Grounding bolt (M4)NOTE
 The grounding bolt is marked with thesymbol.

55 / 105<Remote sensor head (GD-3)>

Grounding bolt (M4)

4. Installation

4-7 Connecting the power and signal cables

4-7 Connecting the power and signal cables
4-7-1

Main unit cable and device connectors

The cable and device connectors on the main unit are as follows:<SD-3>・Power supply and signal
cables, max 2.0 mm2(shielded)
・Lightning arrester (TP-48)<Optional>
・Power supply and signal
cables, max 2.0 mm2(shielded)
・Lightning arrester(TP-48)<Optional>
・HART modem connector(Cannot be used in
explosion-proof areas)

Contact output
max 2.0 mm2 (shielded)<SD-3SC>・Power supply and signal
cables, max 2.0 mm2(shielded)
・Lightning arrester (TP-48)<Optional>
・Power supply and signal
cables, max 2.0 mm2(shielded)
・Lightning arrester(TP-48)<Optional>
・HART modem connector(Cannot be used in
explosion-proof areas)

Contact output
max 2.0 mm2 (shielded)

Remote sensor head (GD-3) connector cable,
max 2.0 mm2 (shielded twisted pair)

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4. Installation

4-7 Connecting the power and signal cables

NOTE
 Use the approved cable glands when connecting the remote sensor head (GD-3).
 Up to two external cable connectors can be used at the same time (excluding the remote sensor head
(GD-3) connector cable). Use the approved cable glands for the connection.
 Blank off unused connectors with blanking plugs.
 Do not use more than one adapter per connector.
 Do not use an adapter together with a blanking plug.

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4. Installation

4-7-2

4-7 Connecting the power and signal cables

Connecting the power and signal cables to the main unit

Connect the power cable, signal cable, and contact cables to the main unit (SD-3/SD-3SC).
1

Unscrew the M4 hex socket set screw on the main unit
cover, then rotate the cover counterclockwise toremove.
Use a hex key wrench (2 across flats) to unscrew the M4
hex socket set screw.
Be careful to avoid dropping the cover while unscrewing andremoving it.

2

Unscrew the two M3 screws securing the display unit.

3

Pull out the display unit and hang on the lug on the
housing.
The display unit is connected to the terminal plate unit by aflat cable. Pulling with excessive force may disconnect thecable.
During the removal process, avoid pulling on the display unit
with excessive force.

4

Lug on housing

Lug on housing

Ground the main unit.
Make sure the grounding is Class D equivalent (grounding
resistance not exceeding 100 Ω). For information on
grounding, refer to ‘4-6 Connecting the grounding terminal’.
Display unit
Grounding bolt

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4. Installation

4-7 Connecting the power and signal cables

5

Attach cable glands or conduits to the connectors on themain unit.
Use appropriate cable glands or conduits to suit the purpose
and type of the cable.

6

Pull out the terminal plates from the terminal plate board.

7

Connect the power and signal cables to the power andsignal terminal plate.
Connect the cables to the following terminals on the powerand signal terminal plate. For more information on thecontact cable connections, refer to ‘4-9 Alarm relay setting(option)’. For information on connecting cables to theterminal plate, refer to ‘4-7-5 Connecting cables to theterminal plate’.

Cable gland

Cable gland

Power and signal
terminal plate

Contact output terminal plates

Crimping terminal

Sheathing

Insulation

Conductor

Recommended insulation length: 40 - 50 mm

When connecting cables, connect the cable shielding to theterminals at the top left or top right on the inside of the mainunit.
Depending on the installation location, noise interference may
result. If this happens, remove the shielding.
8

Connect the required number of contact cables to thecontact output terminal plates.
For information on connecting cables to the terminal plate, referto ‘4-7-5 Connecting cables to the terminal plate’.

*No contact output terminal plate is present with the no contact output option.

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1
2
3
4(The numbers are
terminal numbers.)<Using 3-core cable>
Terminal
Power/signal cable connection
No.
1
Power supply (+)
2
Common (power supply (−), signal (−))
3
Signal (+)<Using 4-core cable>
Terminal
Power/signal cable connection
No.
1
Power supply (+)
2Power supply (−)
3
Signal (+)
4
Signal (−)

1
2
3
4

4. Installation

9

4-7 Connecting the power and signal cables

Mount the terminal plates on the terminal plate board.
Adjust the cable position so that no load is applied to theterminal plates.

Power and signal terminal plate

Contact output terminal plates

10 Return the display unit to its original position andsecure with the two M3 screws.
Take care not to trap the cable here.

11 Rotate the cover clockwise to attach and secure withthe single M4 hex socket set screw.
Use a hex key wrench (2 across flats) to tighten the M4 hex
socket set screw.
Take care not to trap the cable when attaching the cover.
Rotate the cover clockwise until it moves no further tosecurely fasten in place.

*The diagram illustrates the SD-3. The connection method for the SD-3SC is identical.

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4. Installation

4-7-3
1

4-7 Connecting the power and signal cables

Connecting the power and signal cables to the remote sensor head (GD-3)

Unscrew the single M4 screw on the remote sensor head
(GD-3) cover.
Use a hex key wrench (2 across flats) to unscrew the M4 hex
socket set screw.
Be careful to avoid dropping the cover while unscrewing andremoving it.

2

Rotate the cover counterclockwise and remove.

3

Attach a cable gland or conduit to the connector on
the remote sensor head (GD-3).
Use an appropriate cable gland or conduit to suit the
purpose and type of the cable.
Cable gland4

Hex key wrench

Terminal plate

Pull out the terminal plate (TN1) from the terminal plateboard.

Terminalplate

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4. Installation

5

4-7 Connecting the power and signal cables

Connect the power and signal cables to the terminal plate.
Connect the cables to the following terminals on theterminal plate. For information on how to connect cables tothe terminal plate, refer to ‘4-7-5 Connecting cables to theterminal plate’.
Terminal
No.
1
2
3
4

Sheathing

4 3 21

Power/signal cable connection
Power supply (+)
Power supply (−)
Signal (+)
Signal (−)

Insulation(The numbers are
terminal numbers.)

Conductor

Recommended insulation length: 40 - 50 mm

When connecting cables, connect the cable shielding to
the terminals at the top left or top right on the inside of themain unit.
Depending on the installation location, noise interference
may result.
In such cases, remove the shielding.
6

Route the cable from inside the main unit to theconnector.
Route to the connector on the side where the cable glandor conduit is attached.
Cable gland

7

Mount the terminal plate on the terminal plate board.
Adjust the cable position so that no load is applied to theterminal plates.
<With cable (external cable) routed to right-hand side><With cable (external cable) routed to left-hand side>

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4. Installation

8

4-7 Connecting the power and signal cables

Rotate the cover clockwise to attach and secure with thesingle M4 hex socket set screw.
Use a hex key wrench (2 across flats) to tighten the M4 hex
socket set screw.
Take care not to trap the cable when attaching the cover. Rotate
the cover clockwise until it moves no further to securely fasten
in place.

63 / 105

Hex key wrench4. Installation

4-7-4

4-7 Connecting the power and signal cables

Connecting the main unit (SD-3SC) and remote sensor head (GD-3)

1

Unscrew the M4 hex socket set screw on the main unit
(SD-3SC) cover, then rotate the cover counterclockwise
to remove.
Use a hex key wrench (2 across flats) to unscrew the M4
hex socket set screw.
Be careful to avoid dropping the cover while unscrewing andremoving it.

2

Unscrew the two M3 screws securing the display unit.

3

Pull out the display unit and hang on the lug on the
housing.
The display unit is connected to the terminal plate unit by aflat cable. Pulling with excessive force may disconnect thecable.
During the removal process, avoid pulling on the display unit
with excessive force.

Lug on housing

Lug on housing

Display unit

4

Attach a cable gland or conduit to the connector on themain unit.
Use an appropriate cable gland or conduit to suit the
purpose and type of the cable.

Cable gland

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4. Installation

4-7 Connecting the power and signal cables

5

Pull out the remote connection terminal plate from theterminal plate board.

6

Unscrew the single M3 screw securing the clamp
and remove the clamp.

Screw (M3)

Clamp

7

Connect the power and signal cables extending from theremote sensor head (GD-3) to the remote connection
terminal plate.
Connect the cables to the following terminals on the remoteconnection terminal plate. For information on connecting
cables to the terminal plate, refer to ‘4-7-5 Connecting
cables to the terminal plate’.
Terminal
No.
1
2
3
4

Power/signal cable connection
Power supply (+)
Power supply (−)
Signal (+)
Signal (−)

1

2

3

4

(The numbers are
terminal numbers.)
Sheathing

ShieldingInsulation

Conductor

Recommended shielding length: 30 - 40 mm
Recommended insulation length: 130 - 140 mm

8Mount the terminal plate on the terminal plate board.
Adjust the cable position so that no load is applied to theterminal plates.

65 / 105

Remote connection terminalplate4. Installation

9

4-7 Connecting the power and signal cables

Clamp the shield wire.
Use the single M3 screw to clamp the cableshielding.

ShieldingScrew (M3)Clamp

10 Return the display unit to its original position andsecure with the two M3 screws.
Take care not to trap the cable here.

11 Rotate the cover clockwise to attach and secure with thesingle M4 hex socket set screw.
Use a hex key wrench (2 across flats) to tighten the M4 hex
socket set screw.
Take care not to trap the cable when attaching the cover.
Rotate the cover clockwise until it moves no further tosecurely fasten in place.

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4. Installation

4-7 Connecting the power and signal cables＜SD-3SC and GD-3 connection example＞
SD-3SC

Cable glands

GD-3

Cable

<SD-3/SD-3SC and RM-5003 terminal plate connection example>
SD-3/SD-3SC

RM-5003

Shielded cable

1

13

2

12

3

14

4

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4. Installation

4-7 Connecting the power and signal cables<Indicator connection example>
SD-3
Connect the shield to the grounding
bolt on the chassis<SD-3>
Indicator (e.g., RM-5003)

Power supply(+)
CommonSignal (+)

SD-3SC
Connect the shield to the grounding bolton the chassis<SD-3SC>
Indicator (e.g., RM-5003)
Power supply(+)
CommonSignal (+)

Secure shielded cable with clamp.
GD-3
Connect the shield to thegrounding bolt on the chassis

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4. Installation

4-7-5

4-7 Connecting the power and signal cables

Connecting cables to the terminal plate

Strip the cable to the specified length and connect to the cable wire insertion holes on the terminal plate.

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

<Connecting conditions> Cable used: 0.25 mm2 - 2.5 mm2
 Maximum sheathing external diameter: 4.1 mm
 Stripped wire (conductor) length: 8 mm - 9 mm (9 mm - 10 mm for SD-3 TN1 only) Connecting tool: Flathead screwdriver (blade tip 2.5 mm × 0.5 mm) or operating lever (provided)

CAUTIONBe sure to strip the cable to the specified (conductor) length.
 Conduction faults or overheating may result if the stripped wire (conductor) length is too short and thewire is clamped incorrectly.
 Conduction faults or overheating may result if the stripped wire (conductor) length is too short and thewire sheathing is clamped.
 An insulation failure or short circuit may result if the stripped wire (conductor) length is too long and thewire is exposed.
 Make sure the wire does not splay. An insulation failure or overheating may result if the wire splays wheninserted.
 To avoid the above, if the stripped wire is stranded wire cable, we recommend using a bar terminal(ferrule).
9 mm - 10 mm<Compatible rod terminal>
If you use rod terminals, use the following item: Rod terminal (ferrule): Model 216 series (manufactured by WAGO)
 Crimping tool: Model Variocrimp 4 (206-1204) (manufactured by WAGO)

CAUTION Be sure to use the specified rod terminals. We cannot guarantee performance if you use rod terminals
other than those specified.

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4. Installation

4-7 Connecting the power and signal cables<Connecting cables to terminal plate>
To connect cables to the terminal plate, use the operating lever provided as a standard accessory or a flatheadscrewdriver (blade tip 2.5 mm × 0.5 mm).
The operating lever provided as a standard accessory cannot be used when connecting power and signal
cables to TN1 on the SD-3. Use a flathead screwdriver in this case.

CAUTION Be sure to use the correct tools.
 As a rule, only one cable can be connected to each wire insertion hole.
 If a cable is inserted into the screwdriver slot, the conductor may not make contact, resulting in
conduction faults or overheating.

When using the operating lever provided as a standard accessory, connect the cable to the terminal plate as
follows.
1

Hook the operating lever on to the screwdriverslot (rectangular hole) in the terminal plate as
shown in the figure to the right.

2

Push the operating lever with your finger to pushdown the spring inside the terminal plate.

Screwdriver slot

Operatinglever

3

While continuing to press the operating lever, insert
the cable into the wire insertion hole (round hole)until it contacts the end.

4

Release the operating lever.
The cable is now connected to the terminal plate.
Gently pull on the cable to confirm that it is correctly connected.
Avoid pulling with excessive force.

70 / 105

Wire insertion
hole
Cable

4. Installation

4-7 Connecting the power and signal cables

When using a flathead screwdriver to connect to TN1 on the SD-3, connect the cable to the terminal plate as
follows:1

Insert the flathead screwdriver into thescrewdriver slot (rectangular hole) in the terminal
plate as shown in the figure to the right.

Flatheadscrewdriver
Screwdriver slot
Wire
insertionhole

2With the flathead screwdriver still being inserted,
insert the cable into the wire insertion hole (roundhole) until it contacts the end.
Cable

3

Release the flathead screwdriver.
The cable is now connected to the terminal plate.
Gently pull on the cable to confirm that it is correctly connected.
Avoid pulling with excessive force.

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4. Installation

4-8 Mounting the sensor

4-8 Mounting the sensor
Mount the sensor on to the main unit (SD-3) or remote sensor head (GD-3).
1

Remove suction cap, splash guard, and filter, if fitted.

2

Unscrew the single M4 bolt securing the sensor guard.
Use a hex key wrench (2 across flats) to unscrew the M4
hex socket set screw.

Sensor guard
Hex key wrench

3

Rotate and remove the sensor guard.
Remove using a hex key wrench (8 across flats) or
wrench.

4

Pull out and remove the sensor, if fitted.

SensorSensor guard
Hex key
wrench5Match the main unit connector and sensor connector
and fully insert the sensor.
Push the sensor all the way into the main unit connector.
Avoid forcibly turning or pushing in the sensor wheninserting it, as this may damage the main unit. Take carewhen inserting.

Main unit connector

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4. Installation

6

4-9 Alarm relay setting (option)

Confirm that the sensor is fully inserted.

SensorSensor is not fully
inserted.

7

Attach the sensor guard to the main unit.
Attach using a hex key wrench (8 across flats) or wrench.

8

Use the single M4 hex socket set screw to secure the sensor
guard in place.
Use a hex key wrench to tighten the M4 hex socket set screw.

*The diagram illustrates the SD-3. The mounting method for the remote sensor
head (GD-3) is identical.

Sensorguard

Hex key wrench

CAUTION Depending on the sensor, some fluctuation of the reading may occur if foreign objects are introduced
while replacing the sensor.

4-9 Alarm relay setting (option)
The product can be operated as a standalone unit by setting an alarm relay.
By default, the alarm relay is set to a de-energized state.

WARNING If using a supply voltage of 30 V AC or 42.4 V DC or greater, either fit protective tubing to the cable or use
a double insulation cable.

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4. Installation

4-9 Alarm relay setting (option)

CAUTION Note that recurring use with the alarm relay contacts normally closed may result in the contacts seizing
due to minute vibrations.
 Connect the alarm relay cable and sensor before turning on the power to the product.
To set the alarm relay, connect the alarm unit cables to the TN2 (Relay1), TN3 (Relay2), and TN4 (Relay3)
terminal plates on the main unit (SD-3/SD-3SC).
1

Unscrew the M4 hex socket set screw on the main
unit cover, then rotate the cover counterclockwise
to remove.
Use a hex key wrench (2 across flats) to unscrew theM4 hex socket set screw.
Be careful to avoid dropping the cover while unscrewing
and removing it.

Lug on housing

2

Unscrew the two M3 screws securing the display
unit.

3

Pull out the display unit and hang on the lug on the
housing.
The display unit is connected to the terminal plate unit
by a flat cable. Pulling with excessive force may
disconnect the cable.
During the removal process, avoid pulling on the display
unit with excessive force.

Lug on housing

Display unit

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4. Installation

4-9 Alarm relay setting (option)

4

Pull out the terminal plates (TN2 (Relay1), TN3(Relay2), and TN4 (Relay3)) from the terminal plateboard.

5

Connect the alarm unit wires to the corresponding
terminals on the detached terminal plates.
Use either terminal 1 (N.O.) or terminal 3 (N.C.) on theterminal plate.
TN3
For information on how to connect cables to the terminal
plates, refer to ‘4-7-5 Connecting cables to the terminal
plate’.
Common for TN2 (Relay1), TN3 (Relay2), and TN4(Relay3)(Default (normally de-energized) terminal assignment)
Terminal
No.
1
2
3

TN2

TN4

Cable connection
N.O.
CommonN.C.

N.O.: Normally open
N.C.: Normally closed

Conductor
Insulation
SheathingRecommended insulation length: 120 - 130 mm

6

Mount the terminal plates (TN2 (Relay1), TN3 (Relay2),
and TN4 (Relay3)) on the terminal plate board.
Adjust the cable position so that no load is applied to theterminal plates.

7

Return the display unit to its original position andsecure with the two M3 screws.
Take care not to trap the cable here.

8

Rotate the cover clockwise to attach and secure withthe single M4 hex socket set screw.
Use a hex key wrench (2 across flats) to tighten the M4
hex socket set screw.
Take care not to trap the cable when attaching the cover.
Rotate the cover clockwise until it moves no further tosecurely fasten in place.

*The diagram illustrates the SD-3. The connection method for the SD-3SC is
identical.

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4. Installation

4-10 Mounting the splash guard

4-10 Mounting the splash guard
When using a silicone removal filter or activated carbon filter, fit the filter inside the splash guard before mounting
the splash guard.
1

2

When using a silicone removal filter or activatedcarbon filter, remove the splash guard cover, fit thefilter inside the splash guard, and reattach the cover.
This step is required only when using a silicone removal
filter or activated carbon filter.

Cover

FilterMount the splash guard over the guard on the mainunit, then turn clockwise to secure into place.
Mount the splash guard securely by rotating clockwise
until it will not rotate any further.
Avoid rotating with excessive force.

Guard

Splash guard*The diagram illustrates the SD-3. The mounting method for the remote sensor head (GD-3) is identical.

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4. Installation

4-10 Mounting the splash guard

NOTE Three different splash guard types are available: for the IRF sensor; forthe combustible gas sensor; and for the ESF sensor.
The corresponding identification number is engraved on theunderside of each splash guard.
Identification
・ IRF sensor identification number:
1
number・ Combustible gas sensor identification number: 2
・ ESF sensor identification number:3
 The splash guards are compatible with the following SD-3 and GD-3 models:<for combustible gas<for IRF sensor><for ESF sensor>
sensor>SD-3RI
SD-3NC
SD-3ECGD-3RI
SD-3GH
SD-3ECB
SD-3GHSGD-3EC
SD-3SP
GD-3ECB
GD-3NCGD-3GH
GD-3GHS
GD-3SP

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5. Usage Instructions

5-1 Preparations for startup

5

Usage Instructions
5-1 Preparations for startup
Carry out the following checks before connecting the power supply. Failure to perform these checks may resultin electric shock or damage to the product.
 Check to confirm that the product is grounded.
 Check to confirm that external wiring is correctly connected.
 Check to confirm that the power supply voltage is within the rated range.
 External contacts may operate while adjustment is under way. Take precautions to prevent any external
effects from the contacts operating.

<How to read display examples>
LED display examples are shown as follows in this operating manual.
The display examples are for cases in which the detection target gas is combustible gas (display units: %LEL
lit).
PW

A1

A2

PPM %LEL %F

PW:POWER (Power lamp)lit (green) /A1:

ALM1 (Alarm lamp)lit (red)A2:

ALM2 (Alarm lamp)lit (red)F:

FAULT (Fault lamp)lit (yellow)

PPM:

Units lamplit (green)%LEL: Units lamplit (green)%:lit (green)

Units lamp

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flashing (green)5. Usage Instructions

5-2 Startup

5-2 Startup
CAUTION Check to confirm that the product has been correctly installed before turning on the power supply (24 V
DC).

Turn on the power supply (24 V DC) and start the product.
The product takes approximately 25 seconds before switching to detection mode after the power is turned on.
System checks, alarm cutoff, and other initialization occurs during this time.
The display automatically changes as follows after the power is turned on.
The product is normally used in detection mode after the power is turned on.

RINC
All lit

GH

EC
Initialization display (approx. 25 seconds)

Detection modeSP
All lit

Initialization display(approx. 25 seconds)

Initialization
display(The number indicates
the warmup time)

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Detection mode

5. Usage Instructions

5-2 Startup

CAUTION Never turn off the power while initialization is underway. The internal memory is read during initialization.
 A specific warmup is required for each sensor type at startup and after sensor replacement. Allow the
product to warm up for the specified time. Expected warmup completion times for the semiconductor type(SGF) and hot-wire semiconductor type (SHF) sensors are indicated after initialization. Alarm activationand output signals will be unstable during warmup. Notify the relevant department beforehand to avoid
conditions that may lead to errors.
 Perform calibration once warmup is complete.

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5. Usage Instructions

5-3 Basic operation flow

5-3 Basic operation flow
After the power is turned on, the product operates as follows when you press the MENU/ESC key:
<Detection mode>
MENU/ESC key(long press)
Power is turned backon after recovery.
MENU/ESC key(long press)<First alarm><User mode><Second alarm><Maintenance mode><Fault alarm>

WARNING Switching from detection mode to user mode or maintenance mode in an alarm state will cancel thealarm.

NOTE
 The LEDs on the product comprise a five-digit seven-segment display. Setting details are displayed as
item numbers.
When setting in user mode or maintenance mode, select the item number corresponding to the details tobe set. (Refer to ‘5-5-1 User mode setting items’ and ‘7-2-1 Maintenance mode setting items’ in theTechnical manual.)

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5. Usage Instructions

5-4 Operating procedure

5-4 Operating procedure
The product is operated using the control key.
Use the control key to touch the four keys (MENU/ESC key, SET key, ▲ key, and ▼ key) on the front of the
product.
This operating manual refers to the action of touching the individual keys using the control key as “pressing.”<Control key>

CAUTION Do not press the control key forcibly against the glass.

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5. Usage Instructions

5-5 User mode

5-5 User mode
Switching to user mode lets you perform zero calibration and check various settings.

CAUTION Do not alter settings unnecessarily. Altering the settings without a proper understanding of the details
may prevent the product from operating correctly.

5-5-1

User mode setting items

Item No.
1-0

Setting item
Version information

1-1

Zero calibration

Performs zero calibration.
(Refer to ‘5-6 Performing zero
calibration’.)1-2

Setting display

Displays the alarm settings.
(Refer to ‘5-7 Checking settings’.)

1-3

Maintenance mode
selection

Switches to maintenance mode.
(Refer to ‘7-2 Maintenance mode’ inthe Technical manual.)

LED display

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Details
Displays the program version andother information.
This is not normally used by theuser.

5. Usage Instructions

5-5-2
1

5-5 User mode

Switching to user mode

Hold down the MENU/ESC key (for approximately threeseconds) in detection mode.

The product switches to user mode.

2

Press the ▲ or ▼ key to select the required item
number, then press the SET key.

Display example: With setting
display selected

The details corresponding to the item number selected are displayed.
Set or display individual items.

3

Once the operation is complete, hold down the MENU/ESC key (for approximately three seconds).
The product switches to detection mode.

WARNING Once the operation is complete, be sure to hold down the MENU/ESC key to return to detection mode.
The product will not detect gases while in adjustment/setting state. If left in user mode, the product willtake 10 hours to return to detection mode. Detection will not be available during this time, posing
hazards.

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5. Usage Instructions

5-6 Performing zero calibration

5-6 Performing zero calibration
This performs the zero calibration required to ensure accurate measurement of gas concentrations.
Prepare the zero calibration gas, then connect to the product before starting zero calibration.
For information on zero calibration preparation, refer to ‘7-4-1 Calibration preparation’ in the Technical manual.

WARNING Before performing zero calibration for the surrounding atmosphere, confirm that the surrounding
atmosphere contains clean air. Performing zero calibration in the presence of miscellaneous gases will
prevent correct calibration and create safety hazards in the event of an actual gas leak.

CAUTION Perform zero calibration after supplying the zero calibration gas and waiting for the reading to stabilize.

1

Press the ▲ or ▼ key in user mode to select [1-1], thenpress the SET key.

2

Introduce the zero calibration gas, then press the SET key.

Zero calibration starts.

3

Check the zero calibration result.
If zero calibration is successful[PASS] is displayed for three seconds before the display automatically
returns to [1-1].
If zero calibration is unsuccessful[FAIL] is displayed for three seconds before the display automatically
returns to [1-1].

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5. Usage Instructions

5-6 Performing zero calibration

NOTE If zero calibration is unsuccessful because the zero point ([20.9] (vol%) in the case of oxygen) fluctuatessignificantly around zero, [FAIL] is displayed before the display returns to [1-1]. If this occurs, zero
calibration was not performed.
 [1-1] corresponds to span adjustment for the oxygen deficiency alarm specifications. Introduce clean air
to adjust to [20.9] (vol%). For information on span adjustment, refer to ‘7-4-3 Performing span
adjustment’ in the Technical manual.

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5. Usage Instructions

5-7 Checking settings

5-7 Checking settings
Displays the alarm settings.
Item No.
1-2
1-2.0

1-2.1

5-7-1

Setting item
Setting display
Alarm setting display‐

Remarks
Zero follower setting ON/OFF display:NC

Sensitivity correction ON/OFF display:

EC

EC

This is not normally used by the user.

Checking alarm setpoints

Displays the various alarm settings, including first alarm setpoint, second alarm setpoint, and alarm delay time.

NOTE The zero follower setting ON/OFF display appears only with sensors that rely on the new ceramic orelectrochemical detection principle. (Refer to ‘1-2-2 Detection principles and detection target gases forindividual models’.) The sensitivity correction ON/OFF display appears only with sensors that rely on the electrochemical typedetection principle. (Refer to ‘1-2-2 Detection principles and detection target gases for individual models’.)

1

Press the ▲ or ▼ key in user mode to select [1-2], thenpress the SET key.

2

Select [1-2.0], then press the SET key.

3

Check the individual alarm setpoints.
Press the ▲ or ▼ key to toggle between different setpoints.
・ First alarm setpoint display
Displays the first alarm setpoint.

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5. Usage Instructions

5-7 Checking settings

・ Second alarm setpoint display
Displays the second alarm setpoint.

・ Alarm delay time
Displays the alarm delay time (in seconds).

・ Zero suppression value display
Displays the positive side suppression value.

・ Zero follower ON/OFF display
Displays whether the zero follower setting is on or off.
(This is not normally used by the user.)・ Sensitivity correction ON/OFF display
Displays whether sensitivity correction is on or off.
(This is not normally used by the user.)Press the ▲ key to return to the first alarm setpoint display.
First alarm setpoint display
4

Press the MENU/ESC key.
Returns to the [1-2.0] display.

NOTE
 The alarm setpoints, alarm delay time, and zero suppression value can be set in environmental settings 1
in maintenance mode. (Refer to ‘7-5 Setting environmental settings 1’ in the Technical manual.)

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5. Usage Instructions

5-8 Shutting down

5-8 Shutting down
To shut down product operation, turn off the power supply (24 V DC) while in detection mode.

WARNING Shutting down product operation may activate an alarm in an upstream (central) system.
 Before shutting down product operation, make sure the INHIBIT setting is enabled (alarm processes are
stopped) in the upstream (central) system. Also check the operation of any devices connected to theexternal output or external contact output terminal of the product to confirm shutting down the power will
not cause problems.
 If using contacts (optional), the contacts may activate when the power supply is turned off.

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6. Storage, Relocation, and Disposal

6-1 Procedures for storage or when not in use for extended periods

6

Storage, Relocation, andDisposal
6-1 Procedures for storage or when not in use for extended
periods
The product must be stored in the following environment: In a location at normal temperatures and humidity and away from direct sunlight In a location free of gases, solvents, and vapor<Storage conditions (Sensor)>
Model

Storagelimit(years)－Temperature(°C)

Humidity*1(% RH)

Pressure(kPa)

Remarks

Minimum Maximum Minimum Maximum Minimum Maximum

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

IRF

0.5

-10

40

0

90

80

120

ESF

0.5

-10

40

0

90

80

120

・ The sensor must be stored in the specified
packing case.
・ Store in a location away from 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 act as a catalyst poison (e.g., silicone,chlorine, sulfur gases).
・ The sensor must be stored in the specified
packing case.
・ Store in a location away from direct
sunlight.
・ Store in an environment free of corrosive
gas, vibration, and dust.
・ Avoid condensation and moisture.
・ The sensor must be stored in the specified
packing case.
・ Store in a location away from 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 act as a catalyst poison (e.g., silicone,chlorine, sulfur gases).

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

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6. Storage, Relocation, and Disposal

6-1 Procedures for storage or when not in use for extended periods<Storage conditions (Sensor-fitted SD-3)>
Storage

Model

limit
(years)－Temperature(°C)

Humidity*1(% RH)

Pressure(kPa)

Minimum Maximum Minimum Maximum Minimum Maximum

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

IRF

0.5

-10

40

0

90

80

120

0.5

-10

40

0

90

80

120

0.5

-10

40

0

90

80

120

ESF-A*2

ESF-X*3

ESF-B*4

Remarks
・ Store in a location away from direct
sunlight.
・ Store in an environment free ofcorrosive gas, vibration, and dust.
・ Avoid condensation and moisture.
・ Store in an environment free ofgases that may act as a catalyst
poison (e.g., silicone, chlorine, sulfur
gases).
・ Store in a location away from direct
sunlight.
・ Store in an environment free ofcorrosive gas, vibration, and dust.
・ Avoid condensation and moisture.
・ Store in a location away from direct
sunlight.
・ Store in an environment free ofcorrosive gas, vibration, and dust.
・ Avoid condensation and moisture.
・ Store in an environment free ofgases that may act as a catalyst
poison (e.g., silicone, chlorine, sulfur
gases).
・ Store in the dedicated sensor storage
container.*5
Open the dedicated container justbefore use, remove the sensor, andmount in the detector.

*1: Maximum humidity corresponds to an absolute humidity of 33 g/m3 (33.6 °C, 90 %RH).
*2: ESF-A refers to sensor model names starting with “ESF-A”.
*3: ESF-X refers to sensor model names starting with “ESF-X”.
*4: ESF-B refers to sensor model names starting with “ESF-B”.
*5: If not stored in the container, fluid leakage may occur under high humidity conditions of 90 %RH or more. Fluid
shortage may occur with the ESF-B*4 under low humidity conditions.

CAUTION This product is very heavy and features various projections. Damage to this product and accompanying
parts may result if they are packaged in general packaging materials. When storing or returning the
product to Riken Keiki for any reason, use the packaging in which the product was shipped. If the original
packaging is no longer available, wrap twice and place hard objects in the spaces within the packaging toensure that the product will not shift inside the packaging. Avoid packaging fragile items.

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6. Storage, Relocation, and Disposal

6-2 Procedures for relocation or reuse

6-2 Procedures for relocation or reuse
Before relocating and resuming use of the product, refer to ‘4-1 Installation precautions’ for information on
relocation locations.
For information on installation procedures, refer to ‘4. Installation’.

CAUTION Calibration must always be performed before resuming use of the product that has been relocated orpreviously stopped and stored. Contact Riken Keiki for information on readjustment procedures, including
calibration.

6-3 Product disposal
Dispose of the product as industrial waste (incombustible) in accordance with local regulations.

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7. Troubleshooting

7-1 Product abnormalities

7

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
Riken Keiki.

7-1 Product abnormalities
Symptom/display

FAULT
lamp

The power cannot
be turned on.

―

Abnormaloperation

Cause

Action

The wires are incorrectly
connected.

Wire correctly.

The wires are detachedfrom the terminal plate.

Connect correctly.

Abnormalities or
instantaneousinterruptions in the power
supply circuit

Check to confirm that the rated voltage is
supplied.
Consider use of an uninterruptible power system,
power supply line filter, or insulated transformer,
and add such devices where appropriate.

Cable abnormality(Disconnection, cable notconnected, short circuit)

Check the wiring for the product and peripheraldevices.

Fuse blown

Replacement required. Contact Riken Keiki.

Internal circuit abnormality

Replacement required. Contact Riken Keiki.

Disturbances due tosudden noise, etc.

Turn off the power and restart. If similar
symptoms recur frequently, take appropriate
measures to address the noise source.
If the problem persists even with noise prevention
measures, contact Riken Keiki.

The sensor is notconnected or connected
improperly.

Turn off the power and check the sensor
connection.

A sensor fault has
occurred.

Replace with a new sensor.

Effects of sudden surge
noise

Turn off the power and restart. If similar
symptoms recur frequently, take appropriate
measures to address the noise source.
If the problem persists even with noise prevention
measures, contact Riken Keiki.

―

Sensorabnormality
(E-1)

(lit)

The main unit (SD-3/
Connect internal wiring of the main unit (SD-3/
SD-3SC) or remote sensor SD-3SC) or remote sensor head (GD-3) correctly.
head (GD-3) internal wiring
is connected incorrectly.

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7. Troubleshooting

Symptom/display

7-2 Reading abnormalities

FAULT
lamp

Sensorabnormality
(E-1)
(lit)

Systemabnormality
(E-9)
(lit)
GD-3 abnormality(E-1A)

(lit)

Cause

ActionCable abnormality
between the main unit
(SD-3SC) and remotesensor head (GD-3)

Check the cable between the main unit (SD-3SC)
and remote sensor head (GD-3).

A main unit (SD-3/
SD-3SC) or remote sensor
head (GD-3) fuse has
blown.

Replacement required. Contact Riken Keiki.

Main unit (SD-3/SD-3SC)or remote sensor head
(GD-3) internal circuit
abnormality

Replacement required. Contact Riken Keiki.

4 - 20 mA output
disconnection

Turn off the power and check the 4 - 20 mA
output connection.

Internal ROM, RAM, or
EEPROM fault

Turn off the power and restart. If the problem
persists, replacement is necessary. Contact
Riken Keiki.

The sensor is notconnected or connected
improperly.

Turn off the power and check the sensor
connection.

A sensor fault has
occurred.

Replace with a new sensor.

Effects of sudden surge
noise

Turn off the power and restart. If similar
symptoms recur frequently, take appropriate
measures to address the noise source.
If the problem persists even with noise prevention
measures, contact Riken Keiki.

7-2 Reading abnormalities
Symptom/display
・ The reading
rises (or drops)
and remains
unchanged.
・ A gas alarm istriggereddespite theabsence of agas leak or any
otherabnormalities atthe detection
area.
・ Response is
slow.

FAULT
lamp

Cause

ActionThe sensor zero or
span has altered(drifted).

Perform zero calibration or span adjustment.

Presence of interference
gases

Check for the presence of interference gases
such as solvents and take appropriate action.

Slow leakage

Trace amounts of detection target gas may beleaking. Leaving this unresolved may lead tohazardous conditions. Take the same action
as for gas alarms.

Environmental
fluctuations

Perform zero calibration or span adjustment.

Effects of noise

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

―

If the problem persists even with noise
prevention measures, contact Riken Keiki.

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7. Troubleshooting

Symptom/display

7-2 Reading abnormalities

FAULT
lamp

Systemabnormality
(E-9)

Cause

ActionSudden environmental
changes

Alarm indications may be issued by the productdue to sudden environmental fluctuations (e.g.,temperature).
The product cannot be used in locations where
sudden environmental changes occur frequently.
The user should take appropriate measures.

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.

Clock abnormality

Set the date and time.
Correction may not function correctly if the EC
sensitivity correction function is enabled.
If similar symptoms recur frequently, the internal
clock may be defective. Replace with a newinternal clock.
Contact Riken Keiki.

Ambient temperatures atthe location where theproduct is installed areoutside the operating
temperature range.

The product operating temperature range varies
with the specific detection principle. The productcannot be used outside the operating
temperature range.
The user should take appropriate measures.

The sensor isapproaching the end ofits service life.

We recommend sensor replacement.
Contact Riken Keiki.

―

Outside operating
temperature
range(E-27)―

Sensor life
expiration
warning(E-8)―

Sensor warning
(E-1)

―

Contact Riken Keiki.

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8. Product Specifications

8-1 Detection target gases for individual detection principles

8

Product Specifications
8-1 Detection target gases for individual detection principles
8-1-1
Sensor modelNon-dispersive infrared absorption type (Infrared type)Gas nameGassymbolFirst

SecondF.S.

1 digitAlarm
setpointAlarm
setpoint

Calibrationgas

IRF-1301*

MethaneCH4

100 %LEL

0.5 %LEL

25 %LEL

50 %LELCH4

IRF-1303*

Isobutane

i-C4H10

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

i-C4H10

IRF-1315*

Propane

C3H8

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

IRF-1435

Carbon dioxide

CO22,000 ppm

1 ppm

1,000 ppm-

CO2

IRF-1436

Carbon dioxide

CO25,000 ppm

10 ppm

1,000 ppm-

CO2

IRF-1433

Carbon dioxideCO210,000 ppm

10 ppm

1,000 ppm-

CO2

IRF-1437

Carbon dioxide

CO2

2 vol%

0.005 vol%

1 vol%-

CO2

Operatingtemperature
range

Operatinghumidity
range

Years ofwarranty

C3H8
i-C4H10

IRF-1438

Carbon dioxide

CO2

5 vol%

0.010 vol%

1 vol%-CO2

IRF-1439

Carbon dioxide

CO2

10 vol%0.01 vol%

1 vol%-CO2

IRF-1334*

MethaneCH4

100 vol%

0.5 vol%

25 vol%50 vol%CH4

IRF-1316*

Ethylene

C2H4

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

IRF-1340*

Isobutylene

i-C4H8

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

IRF-1308*

n-hexanen-C6H14

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

IRF-1332*

Butadiene

C4H6

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL−40 °C 70 °C

95 %RH or
less(no conden-

3 yearssation)C2H4CH4i-C4H8i-C4H10n-C6H14i-C4H10
C4H6
CH4*Interference occurs due to other hydrocarbon gases.

NOTE
 Install in a location with stable conditions within the specified operating temperature range and free of
sudden fluctuations.
 When calibrating, allow the product to warm up for at least 10 minutes before performing zero calibrationand span adjustment.
 Make sure temperature, humidity, and pressure conditions in the calibration environment are the same as
for the measurement environment. (The reading may fluctuate due to temperature, humidity, and96 / 105

8. Product Specifications

8-1 Detection target gases for individual detection principles

pressure characteristics and in some cases may exceed the zero suppression value due to sensor
characteristics.)
 For ethylene or butadiene to which the product has low gas sensitivity, set the alarm setpoint to 25 %LEL
or higher.
 Due to infrared absorption characteristics, readings may differ even for the same target gas concentration
if the base gas composition differs significantly between calibration and measurement—for example, if an
air base is used for calibration and a CO2 base is used for measurement.
 Perform maintenance if a warning appears while the life assessment or self-diagnostic function is active.
 Regardless of the detection target gas, the warranty period for IRF sensors is 3 years.

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8. Product Specifications

8-1-2

8-1 Detection target gases for individual detection principles

New ceramic type

Sensor model Gas nameGas
symbolF.S.

1 digitFirst

Second

Alarm

Alarm

setpoint

setpoint

Calibrationgas

NCF-6318

MethaneCH4

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

CH4*2

NCF-6319

VCM

VCM

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

i-C4H10

NCF-6320

HydrogenH2

100 %LEL

0.5 %LEL

25 %LEL

50 %LEL

OperatingOperatingtemperaturehumidity

range

range

−40 °C 70 °C

Years ofwarranty

0 %RH 95 %RH*1 (no3 years

condensation)

H2*3*1: Absolute humidity not exceeding 46 g/m3 (equivalent to 37 °C, 95 %RH)
*2: Use the NCF-6318 if methane calibration is required or when the detection target gas is methane, propane, or
ethane. The detection target gas overlaps for the NCF-6318 and NCF-6319. Use the NCF-6319 in cases other than
the above.
*3: Use the NCF-6320 if hydrogen selectivity is required.

NOTE
 Install in a location with stable conditions within the specified operating temperature range and free of
sudden fluctuations.
 The sensor characteristics may deteriorate significantly if silicone gases (organic silicone gases), halogen
gases, sulfide gases, or acid gases are present.
 A silicone removal filter and activated carbon filter are available as options.
 For models with a F.S. of 5,000 ppm or less, allow the product to warm up for at least 120 minutes inclean air before performing zero calibration and span adjustment.
 For models with a F.S. of 5,000 ppm or less, the effects of ambient humidity and temperature fluctuations
will become more significant, and the zero point may drift. If this occurs, enable the zero follower function.
However, we recommend using a sensor with a different detection principle where gas is constantly
present. The zero follower function cannot be used under such conditions.
 The reading may change even for combustible gases other than the detection target gas.
 Readings may fall as oxygen concentrations decrease.
 Interference may occur if gases with high thermal conductivity, such as high-concentration CO2, Ar, or He,
are present as the base gas.
 In detecting gases with low vapor pressure by the suction method, the gas may form a mist when drawn
in from the high-temperature side and detected at the low-temperature side, possibly forming
condensation inside the sensor or causing clogging due to sintering. Keep vapor pressure in mind duringuse.
 Perform maintenance if a warning appears while the life assessment or self-diagnostic function is active.
 Use the combustible gas sensor adapter when calibrating. Calibration accuracy may be reduced without
the combustible gas sensor adapter.
 Reading accuracy may be reduced if temperature fluctuations exceed ±40 °C with respect to ambient
temperature following zero calibration or span calibration. If this occurs, repeat zero calibration or span
adjustment.
 Readings may fluctuate if the product is subjected to strong external impact or vibration. If this occurs,
perform zero calibration and span adjustment.
 The zero point may fluctuate if the sensor comes into contact with high-concentration gas of 100 %LEL or
more continuously 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 thesensor is hot, turn off the power and wait for it to cool.
 Regardless of the detection target gas, the warranty period for NCF sensors is 3 years.

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8. Product Specifications

8-1-3
Sensormodel
SGF-8581
SGF-8562

SGF-8563

SGF-8562

8-1 Detection target gases for individual detection principles

Semiconductor typeGas name

MethaneCarbondisulfide
Ethylene
oxide
HydrogensulfideGas
symbolF.S.

1 digitFirst

Second

Alarm

Alarm

setpoint

setpoint

Calibration
gas

CH4

2,000 ppm

10 ppm

500 ppm

1,000 ppm

CH4

CS2

200 ppm

1 ppm

50 ppm100 ppm

CS2

OperatingOperatingtemperaturehumidity

range

range

20 %RH −20 °C - 65 °C

EO

100 ppm

1 ppm

25 ppm50 ppmEO

Years ofwarranty

95 %RH*(no

3 years

condensation)
H2S

100 ppm

1 ppm

25 ppm50 ppm

H2S*Absolute humidity not exceeding 46 g/m3 (equivalent to 37 °C, 95 %RH)

NOTE
 The sensor characteristics may deteriorate significantly if silicone gases (organic silicone gases), halogen
gases, sulfide gases, or acid gases are present.
 A silicone removal filter and activated carbon filter are available as options.
 Prepare the calibration gas to suit the humidity of the environment in which it will be used.
 When calibrating, allow the product to warm up for a period of time corresponding to the length of time
turned off in clean air before performing zero calibration and span adjustment. For information on
appropriate warmup times, refer to the <Semiconductor type sensor warmup times> table below.
 The reading may change even for combustible gases other than the detection target gas.
 The reading may change even for ambient fluctuations (e.g., temperature and humidity) in the installation
location.
 The reading may fall as the oxygen concentration decreases.
 Interference may occur if gases with high thermal conductivity, such as high-concentration CO2, Ar, or He,
are present as the base gas.
 In detecting gases with low vapor pressure by the suction method, the gas may form a mist when drawn infrom the high-temperature side and detected at the low-temperature side, possibly forming condensation
inside the sensor or causing clogging due to sintering. Keep vapor pressure in mind during use.
 Perform maintenance if a warning appears while the life assessment or self-diagnostic function is active.
 Use the combustible gas sensor adapter when calibrating. Calibration accuracy may be reduced without
the combustible gas sensor adapter.
 Reading accuracy may be reduced if temperature fluctuations exceed ±20 °C with respect to ambient
temperature following zero calibration or span calibration. If this occurs, repeat zero calibration or span
adjustment.
 Readings may fluctuate if the product is subjected to strong external impact or vibration. 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 thesensor is hot, turn off the power and wait for it to cool.
 The top of the sensor has a Teflon coating. Sensor characteristics may be affected if the Teflon coating isdamaged. Take care to avoid pressing on the Teflon coating with excessive force or damaging it withsharp implements.
 Calibration is not possible if the reading during calibration does not exceed the zero suppression value.
If the reading is below the zero suppression value when the desired calibration gas is introduced forcalibration, first calibrate using a gas that gives a reading higher than the zero suppression value, thencalibrate using the desired calibration gas.
 Regardless of the detection target gas, the warranty period for SGF sensors is 3 years.

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8. Product Specifications

8-1 Detection target gases for individual detection principles<Semiconductor type sensor warmup times>
Time turned off
Under 10 minutes
Under 1 hour
Under 24 hours
Under 72 hours
Under 10 days
Under 1 month
Under 3 months
3 months or more

SGF-8581
At least 1 hours
At least 2 hours
At least 4 hours
At least 24 hours
At least 2 days
At least 7 days
At least 14 days
At least 1 month

Warmup time
Other SGF sensors
At least 30 minutes
At least 2 hours
At least 4 hours
At least 24 hours
At least 2 days
At least 7 days
At least 14 days
At least 1 month

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8. Product Specifications

8-1-4
Sensormodel
SHF-8601
SHF-8601

8-1 Detection target gases for individual detection principles

Hot-wire semiconductor typeGas name

MethaneCarbonmonoxideGas
symbolF.S.

1 digitFirst

Second

Alarm

Alarm

setpoint

setpoint

Calibration
gas

OperatingOperatingtemperaturehumidity

range

range

CH4

5,000 ppm

25 ppm

2,000 ppm

4,000 ppm

CH4

−30 °C - 70 °C

CO

1,000 ppm

10 ppm

250 ppm

500 ppm

CO

0 °C - 70 °C

Years ofwarranty

20 %RH 95 %RH*
(noSHF-8602

Isobutane

i-C4H102,000 ppm

10 ppm

500 ppm

1,000 ppm

i-C4H10−30 °C - 70 °C

SHF-8603

HydrogenH2

2,000 ppm

10 ppm

500 ppm

1,000 ppm

H2

−30 °C - 70 °C

3 years

condensation)*Absolute humidity not exceeding 46 g/m3 (equivalent to 37 °C, 95 %RH)

NOTE
 The sensor characteristics may deteriorate significantly if silicone gases (organic silicone gases), halogen
gases, sulfide gases, or acid gases are present.
 A silicone removal filter and activated carbon filter are available as options.
 Prepare the calibration gas to suit the humidity of the environment in which it will be used.
 When calibrating, allow the product to warm up for a period of time corresponding to the length of time
turned off in clean air before performing zero calibration and span adjustment. For information on
appropriate warmup times, refer to the <Hot-wire semiconductor type sensor warmup times> table below.
 The reading may change even for combustible gases other than the detection target gas.
 The reading may change even for ambient fluctuations (e.g., temperature and humidity) in the installation
location.
 The reading may fall as the oxygen concentration decreases.
 Interference may occur if gases with high thermal conductivity, such as high-concentration CO2, Ar, or He,
are present as the base gas.
 In detecting gases with low vapor pressure by the suction method, the gas may form a mist when drawn
in from the high-temperature side and detected at the low-temperature side, possibly forming
condensation inside the sensor or causing clogging due to sintering. Keep vapor pressure in mind duringuse.
 Perform maintenance if a warning appears while the life assessment or self-diagnostic function is active.
 Use the combustible gas sensor adapter when calibrating. Calibration accuracy may be reduced without
the combustible gas sensor adapter.
 Reading accuracy may be reduced if temperature fluctuations exceed ±20 °C with respect to ambient
temperature following zero calibration or span calibration. If this occurs, repeat zero calibration or span
adjustment.
 Readings may fluctuate if the product is subjected to strong external impact or vibration. 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 calibration value may become offset if gas is detected at levels exceeding the F.S. value. Enabling
the sensor protection function will help reduce these effects if there is any possibility of exposure to gas at
levels exceeding the F.S. value. However, if the sensor protection function is enabled, detection is notpossible after the F.S. value has been exceeded until it is reset, as the power to the sensor is cut off.
Reset from the sensor protection state in an environment with clean air.
If the sensor protection state has been used for extended periods (one day or longer), warm up for aperiod of time corresponding to the sensor protection period. (Enabling the sensor protection function
also enables the over locking function.) The sensor may be hot during replacement. Be careful to avoid burns when replacing the sensor. If thesensor is hot, turn off the power and wait for it to cool.
 Depending on the conditions and length of time for which the power was turned off, the reading maychange when the power is turned on, even after the warmup time (three minutes) has elapsed. If thisoccurs, wait until the reading returns to zero.
 Regardless of the detection target gas, the warranty period for SHF sensors is 3 years.

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8. Product Specifications

8-1 Detection target gases for individual detection principles<Hot-wire semiconductor type sensor warmup times>
Time turned off
Under 10 minutes
Under 1 hour
Under 24 hours
Under 72 hours
Under 10 days
Under 1 month
Under 3 months
3 months or more

Warmup time
SHF-8603
Other SHF sensors
At least 10 minutes At least 1 hour
At least 30 minutes At least 2 hours
At least 1 hour
At least 4 hours
At least 4 hours
At least 24 hours
At least 2 days
At least 2 days
At least 7 days
At least 7 days
At least 14 days
At least 14 days
At least 1 month
At least 1 month*Note that warmup times differ between the SHF-8603 and other SHF sensors.

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8. Product Specifications

8-1 Detection target gases for individual detection principles

8-1-5

Electrochemical type

Sensor modelGas name

ESF-A24R

ESF-A24RH*3

HydrogensulfideHydrogensulfideGas
symbolF.S.

1 digitFirst

Second

Alarm

Alarm

setpoint

setpoint

20 ppm40 ppmCalibration
gas

OperatingOperatingtemperaturehumidity

range

range

−40 °C - 70 °C*2

90 %RH (noYears ofwarranty

20 %RH H2S

100 ppm

1 ppm

H2S

3 years

condensation)
40 %RH H2S

30 ppm0.2 ppm

10 ppm20 ppmH2S−40 °C - 70 °C*1

95 %RH (no3 years

condensation)*1: Allow the product to fully adjust to the usage conditions before adjusting if below −25 °C. Can be used for a total of
one week between 40 °C and 70 °C.
*2: Allow the product to fully adjust to the usage conditions before adjusting if below −25 °C. Can be used for a total of
one week between 55 °C and 70 °C.

NOTE Perform maintenance if a warning appears while the life assessment or self-diagnostic function is active.
 Use the ESF sensor adapter when calibrating. Calibration accuracy may be reduced without the ESF
sensor adapter.
 Use a flow rate of 0.5 ± 0.1 L/min when calibrating. Calibration accuracy may be reduced if calibration is
performed using a different flow rate.
 When using a diffusion type detector, gas sensitivity will be affected by ambient wind speeds.
 The number of years of warranty for the ESF sensor depends on the sensor model. Refer to the abovetable.

103 / 105

Product warranty
1. If a fault occurs with the product within three years of the purchase date, with use under normal conditions incompliance with precautions indicated in the operating instructions or on labels affixed to the main unit, repairs
will be cost free.
2. Contact our sales department or your nearest sales office for information on repairs, maintenance, or after-sales
service.
3. You will be charged for costs incurred as the result of service rendered in remote locations.
4. Fees will be charged for repairs in the following cases, even during the warranty period:(a) Fault or damage is attributable to incorrect use or improper repairs or modifications.
(b) Fault or damage following repairs or modifications made at locations other than Riken Keiki or a service
agent specified by Riken Keiki.
(c) Fault or damage is attributable to moving, transporting, falling, dropping, or improper storage occurring
after purchase.
(d) Fault or damage is attributable to external factors, including natural phenomena such as fire, earthquake,flood, or lightning; pollution; abnormal voltage; use of power sources outside of rated ranges (voltage,
frequency), etc.
(e) The fault is attributable to a factor external to this product.
(f) When replacing consumables (batteries, fuses, etc.).

Sensor warranty
1. Replacements will be provided at no charge if a fault occurs within three years of the purchase date or the dateon which a sensor was replaced for a fee (excluding certain sensors), with use under normal conditions incompliance with precautions indicated in the operating instructions or on labels affixed to the main unit.
For information on the length of the warranty for each sensor model, refer to ‘10- 3 Detection target gases
for individual detection principles’.
A precondition of the warranty for sensors requires sensors to be serviced once or more a year from the purchasedate or the date on which a sensor was replaced for a fee.
2. Contact our sales department or your nearest sales office for information about repairs, maintenance, or aftersales service.
3. You will be charged for costs incurred as the result of replacements performed in remote locations.
4. Fees will be charged for replacements made in the following cases, even during the warranty period.
(a) If the product is used in disregard of the precautions provided in the operating instructions, on labels
affixed to the main unit, or elsewhere.
(b) Fault or damage following repairs or modifications made at locations other than Riken Keiki or a service
agent specified by Riken Keiki.
(c) Fault or damage is attributable to moving, transporting, falling, dropping, or improper storage occurring
after purchase.
(d) Fault or damage is attributable to external factors, including natural phenomena such as fire, earthquake,flood, or lightning; pollution; abnormal voltage; use of power sources outside of rated ranges (voltage,
frequency), etc.
(e) The fault is attributable to a factor external to this product.
(f) Changes in the gas sensitivity of the sensor, fault, or damage are due to the effects of coexisting gases(acidic gases, alkaline gases, alcohol, silicone, etc.) in the installation environment.

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Revision History
Issue
0

Revision details
First issue (PT2E-3013)

Issue date
7/14/2023

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