PT0E-10710

Portable Multi-Gas Monitor

GX-2012 Series
GX-2012
GX-2012GT
Operating Manual(PT0-107)

Safety information＜ATEX/IECEx/UKEX specifications＞

The Portable Gas Monitor Model GX-2012 is a gas monitor designed to provide continuous exposure
monitoring of combustible gas (LEL,VOL), oxygen (O2), toxic gas such as carbon monoxide (CO) andhydrogen sulfide (H2S) in hazardous environments. Model GX-2012GT is a gas monitor designed toprovide continuous exposure monitoring of combustible gas (ppm,LEL,VOL), oxygen (O2), toxic gas suchas carbon monoxide (CO).
The gas sample is sucked in by build-in micro pump.
The battery can be selected either Li-ion battery or alkaline dry battery.
Li-ion battery unit is called BUL-2012,BUL-2012(G1) and alkaline dry battery unit is called BUD-2012.
The battery unit can be changed even by the end users.

Specification for safety
・Ex ia IIC T4 Ga (without combustible LEL gas sensor)
・Ex ia IIB T4 Ga (with combustible LEL gas sensor)
II 1 G Ex ia IIC T4 Ga (without combustible LEL gas sensor)
II 1 G Ex ia IIB T4 Ga (with combustible LEL gas sensor)
・Ambient temperature range for use : -20 ºC to +50 ºC・Ambient temperature range during battery charging : 0 ºC to +40 ºC

Electrical data
・Power supply of Li-ion battery unit : BUL-2012,BUL-2012(G1)Powered by single Li-ion cell is from type Maxell INR18650PB1 or SDI
INR1865015M or SONY US18650VT3. Um=17.8V,
to be charged with exclusive charger model BC-2012 or SDM-2012
・Power supply of alkaline battery unit : BUD-2012
Powered by three series AA size alkaline batteries, model LR6 by TOSHIBA.
・Backup battery type CR1220 manufactured by Maxell.

Certificate numbers
・IECEx Certificate number : IECEx DEK 11.0045
・ATEX Certificate number : DEKRA 11ATEX 0123
・UKEX Certificate number : DEKRA 21UKEX 0364

List of standards
・IEC 60079-0: 2017
・IEC 60079-11: 2011

・EN IEC 60079-0:2018
・EN 60079-11:2012

・BS EN IEC 60079-0:2018
・BS EN 60079-11:2012

WARNING・Do not charge in hazardous location.
・Use exclusive charger , model BC-2012 or SDM-2012.
・Do not replace battery unit in hazardous location.
・Do not replace dry batteries in hazardous location.
・Do not attempt to disassemble or alter the instrument.
・Use only battery unit type BUD-2012 with three series connected Alkaline
AA batteries, type LR6 manufactured by Toshiba, or use chargeable battery unit
type BUL-2012,BUL-2012(G1).

INST. No. 0 0 0 0 0 0 0 0 0 0 0
AB C
DE
A: Manufacturing year (0-9)
B: Manufacturing month (1-9,XYZ for Oct.-Dec.)
C: Manufacturing lot
D: Serial number
E: Code of factory
2-7-6 Azusawa, Itabashi-ku, Tokyo, 174-8744, Japan
Phone : +81-3-3966-1113
Fax : +81-3-3558-9110
E-mail : intdept@rikenkeiki.co.jp
Web site : https://www.rikenkeiki.co.jp/

<Contents>

1. Outline of the Product........................................................................................................... 2
1-1. Preface .............................................................................................................................. 2
1-2. Purpose of use .................................................................................................................. 2
1-3. Definition of DANGER, WARNING, CAUTION, and NOTE ............................................... 3
1-4. Method of confirmation for Standards and Explosion proof specification .......................... 3
2. Important Notices on Safety ................................................................................................. 4
2-1. Danger cases .................................................................................................................... 4
2-2. Warning cases .................................................................................................................. 6
2-3. Precautions ....................................................................................................................... 7
3. Product Components ............................................................................................................ 9
3-1. Main unit and standard accessories .................................................................................. 9
3-2. Names and functions for each part ................................................................................... 11
4. How to Use ........................................................................................................................... 15
4-1. Before using the gas monitor ............................................................................................ 15
4-2. Preparation for start-up ..................................................................................................... 15
4-3. Basic operating procedures............................................................................................... 19
4-4. How to start the gas monitor ............................................................................................. 21
4-5. How to detect .................................................................................................................... 25
4-6. Modes ............................................................................................................................... 30
4-7. Air calibration mode ........................................................................................................... 32
4-8. Display/setting mode ......................................................................................................... 34
4-9. How to exit ........................................................................................................................ 44
5. Operations and Functions .................................................................................................... 45
5-1. Gas alarm activation ......................................................................................................... 45
5-2. Fault alarm activation ........................................................................................................ 47
5-3. Other functions .................................................................................................................. 48
6. Maintenance ......................................................................................................................... 50
6-1. Maintenance intervals and items ....................................................................................... 50
6-2. Gas calibration method ..................................................................................................... 51
6-3. How to clean ..................................................................................................................... 52
6-4. Parts replacement ............................................................................................................. 52
7. Storage and Disposal ........................................................................................................... 55
7-1. Procedures to store the gas monitor or leave it for a long time ......................................... 55
7-2. Procedures to use the gas monitor again .......................................................................... 55
7-3. Disposal of products .......................................................................................................... 56
8. Troubleshooting .................................................................................................................... 57
9. Product Specifications .......................................................................................................... 60
9-1. List of specifications .......................................................................................................... 60
9-2. List of accessories............................................................................................................. 64
10. Definition of Terms .............................................................................................................. 651

1 Outline of the Product1-1. Preface

1

Outline of the Product1-1. Preface
Thank you for choosing our portable multi-gas monitor GX-2012 series. Please check that the model
number of the product you purchased is included in the specifications on this manual.
This manual explains how to use the gas monitor and its specifications. It contains information required forusing the gas monitor properly. Not only the first-time users but also the users who have already used the
product must read and understand the operating manual to enhance the knowledge and experience before
using the gas monitor.
Product specifications may be abbreviated in this document as follows.
Japan Ex specification ： Japan specification
ATEX / IECEx / UKEX specifications ： Export specification

1-2. Purpose of use
This gas monitor is a multi gas type that enables simultaneous monitoring of all of the following five types ofgases (up to 4 types of gases, excluding hydrogen sulfide, with GX-2012GT) at the maximum: oxygen,combustible gases, and toxic gases (carbon monoxide and hydrogen sulfide) in the air andhigh-concentration combustible gases (vol%) in N2 and inert gases. The gas monitor can measure two
types of combustible gases, "general combustible gases (HC)," which are used in ordinary factories, oiltankers, etc. and "methane (CH4)," such as city gas and natural gas.
Detection results are not intended to guarantee life or safety in any way.
The gas monitor comes in several types for different combinations of gases to be detected. Check the
specifications of the gas monitor before use and conduct gas detection properly in accordance withpurposes. (See the list of gases to be detected at the end of this operating manual)In addition to this operating manual, an operating manual for the data logger management program(optional) is available for the gas monitor. Contact RIKEN KEIKI, if it is needed.

22 Important Notices on Safety

2-1. Danger cases

DANGER
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 Do replace dry battery in non-hazardous location.
 Do replace battery unit in non-hazardous location.
 Only the following main unit can be connected: GX-2012,GX-2012GT(certification number
TC20170). Inappropriate combinations of models deviate from the range of explosion-proof
certification.
 The specifications of dry battery unit(BUD-2012) is as follows:
Explosion-proof grade:
Ex ia ⅡC T4
Maximum voltage:
4.95 VPower supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 ºC - +50 ºC
 The specifications of lithium ion battery unit(BUL-2012,BUL-2012(G1)) are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 W
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.984 A, andmaximum power of 793 W
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Maximum voltage:
4.25 V
Explosion-proof grade:
Ex ia ⅡC T4
Ambient temperature:-20 ºC - +50 ºC
Battery charging contact:
Allowable voltage of 17.8 V, Allowable current of 2.72 A
 IP protection class of battery units are IP20.
About combination
Make sure that the product model on the nameplate is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
The nameplate shows the followings as well as the product model.
Product model:
Main unit GX-2012,GX-2012GT
Dry battery unit BUD-2012
Lithium ion battery unit BUL-2012,BUL-2012(G1)
Manufacture:
RIKEN KEIKI Co., LTD.
Explosion-proof grade: Ex ia ⅡC T4 X(GX-2012,GX-2012GT)
Ex ia ⅡC T4(BUD-2012,BUL-2012,BUL-2012(G1))
Ambient temperature: -20 ºC - +50 ºC
Warnings: Inhibit to take off battery unit in non-hazardous area. (GX-2012,GX-2012GT)
Inhibit to take off dry battery in non-hazardous area. (GX-2012,GX-2012GT,BUD-2012)
Powered by three series connected Alkaline AA batteries, type LR6 manufactured by Toshiba.

About use While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (100 %LEL or higher) gases may be discharged. Never use fire near the gas
monitor.

5

2 Important Notices on Safety

2-2. Warning cases

2-2. Warning cases
WARNING
Sampling point pressure The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may be leaked from its inside, thus leading to danger. Avoid applying excessive
pressure to the gas monitor while in use.
 Do not connect the taper nozzle directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
Handling of sensor
Do not disassemble the electrochemical type sensor or galvanic cell type sensor because they
contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin, while it may cause
blindness if it contacts eyes.
If electrolyte is adhered on your clothes, that part on your clothes is discolored or its material isdecomposed. If contact occurs, rinse the area immediately with a large quantity of water.
Fresh air adjustment in atmosphere
When the fresh air adjustment is performed in the atmosphere, check the atmosphere for freshness
before beginning the adjustment. If other gases exist, the adjustment cannot be performed properly,
thus leading to dangers when the gas leaks.
Response to gas alarm
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
Battery level check Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either replace thebatteries with new ones or fully charge them before use.
 If a low battery voltage alarm is triggered, gas detection cannot be conducted. If the alarm istriggered during use, turn off the power and promptly replace (recharge) the batteries in a
non-hazardous area.
Others Do not throw the gas monitor into fire.
 Do not wash the gas monitor in a washing machine or ultrasonic cleaner.
 Do not block the buzzer sound opening. No alarm sound can be heard.
 Do not remove the battery unit while the power is ON.
 Do not remove the battery unit in a hazardous location.
 Do not remove the dry batteries in a hazardous location.

6

2 Important Notices on Safety

2-3. Precautions

2-3. Precautions
CAUTION
Do not use the gas monitor where it is exposed to oil, chemicals, etc. Do not submerge the gas
monitor under water on purpose.
 Do not use in a place where the gas monitor is exposed to liquids such as oil and chemicals.
 The gas monitor, being compliant to IP67, is not water-pressure-resistant. Do not use the gas
monitor where a high water pressure is applied to it (under a faucet, shower, etc.) or submerge it
under water for a long time. The gas monitor is water-proof only in fresh water and runningwater, and not in hot water, salt water, detergent, chemicals, human sweat, etc.
 The gas inlet and outlet are not water-proof. Be careful not to let water such as rainwater get into
these parts. Because this may cause trouble and gas cannot be detected.
 Do not place the gas monitor where water or dirt gets accumulated. The gas monitor placed atsuch a location may malfunction due to water or dirt that gets into the buzzer opening, gas inlet,etc.
 Note that drawing in dirty water, dust, metallic powder, etc. will significantly deteriorate thesensor sensitivities. Be careful when the gas monitor is used in an environment where theseelements exist.
Do not use the gas monitor in a place where the temperature drops below -20 ºC or rises over 50 ºC.
 The operating temperature of the gas monitor is -20 - 50 ºC. Do not use the gas monitor at higher
temperatures, humidity, and pressures or at lower temperatures than the operating range.
 Avoid long-term use of the gas monitor in a place where it is exposed to direct sunlight.
 Do not store the gas monitor in a sun-heated car.
Observe the operating restrictions to prevent condensation inside the gas monitor.
Condensation formed inside the gas monitor causes clogging or gas adsorption, which may disturb
accurate gas detection. Thus, condensation must be avoided. In addition to the installation
environment, carefully monitor the temperature/humidity of the sampling point to prevent
condensation inside the gas monitor. Please observe the operating restrictions.
Do not use a transceiver near the gas monitor.
 Radio wave from a transceiver near the gas monitor may disturb readings. If a transceiver orother radio wave transmitting device is used, it must be used in a place where it disturbs nothing.
 Do not use the gas monitor near a device that emits strong electromagnetic waves(high-frequency or high-voltage devices).
Verify that the pump operating status indicator is rotating before using the gas monitor.
If the pump operation status indicator is not rotating, gas detection cannot be performed properly.
Check whether the flow rate is lost.
Verify that the driving status indicator is blinking before using the gas monitor.
If the driving status indicator is not blinking, gas detection cannot be performed properly.
Never fail to perform a regular maintenance.
Since this is a safety unit, a regular maintenance must be performed to ensure safety. Continuing to
use the gas monitor without performing maintenance will compromise the sensitivity of the sensor,
thus resulting in inaccurate gas detection.

7

2 Important Notices on Safety

2-3. Precautions

CAUTION
Others Pressing buttons unnecessarily may change the settings, preventing alarms from activatingcorrectly. Operate the gas monitor using only the procedures described in this operating manual.
 Do not drop or give shock to the gas monitor. The water-proof and explosion-proof properties
and accuracy may be deteriorated.
 Do not use the gas monitor while charging it.
 Whereas the gas monitor can detect oxygen, combustible gases, carbon monoxide, andhydrogen sulfide, the operating environment may include gases that have harmful effects on thesensors of this unit. (Different gases can be detected depending on the type).
The gas monitor cannot be used in the presence of the following gases:(1) Sulfides (such as H2S and SO2) continuously existing in high concentrations(2) Halogen gases (such as chloride compounds and chlorofluorocarbons)(3) Silicone (Si compounds)
Do not use the gas monitor in the presence of the above gases (such as high-concentration
sulfides, halogen gases, and silicone), which may shorten the sensor life significantly or cause
malfunctions such as inaccurate readings.
In case the gas monitor is used for detection in the presence of silicone, etc., be sure to checkthe gas sensitivities before using it again.

8

3 Product Components

3-1. Main unit and standard accessories

DANGER
About explosion-proof of battery unit Do not modify or change the circuit or structure, etc.
 When using this gas monitor in a hazardous area, take the following countermeasures forpreventing dangers resulting from electrostatic charges.
(1) Wear anti-static clothes and conductive shoes (anti-static work shoes).
(2) For indoor use, use the gas monitor while standing on a conductive work floor (with aleakage resistance of 10 MΩ or less).
 Do replace dry battery in non-hazardous location.
 Do replace battery unit in non-hazardous location.
 Only the following main unit can be connected: GX-2012,GX-2012GT(certification number
TC20170). Inappropriate combinations of models deviate from the range of explosion-proof
certification.
 The specifications of dry battery unit(BUD-2012) is as follows:
Explosion-proof grade:
Ex ia ⅡC T4
Maximum voltage:
4.95 VPower supply:
4.5 VDC, 250 mA (Type LR6 manufactured by Toshiba, 3 pcs)
Ambient temperature:-20 ºC - +50 ºC
 The specifications of lithium ion battery unit(BUL-2012,BUL-2012(G1)) are as follows:
Pump circuit:
Maximum voltage of 4.25 V, maximum current of 0.768 A, andmaximum power of 618 W
Main circuit:
Maximum voltage of 4.25 V, maximum current of 0.984 A, andmaximum power of 793 W
Buzzer circuit:
Maximum voltage of 4.25 V, maximum current of 0.410 A, andmaximum power of 330 mW
Maximum voltage:
4.25 V
Explosion-proof grade:
Ex ia ⅡC T4
Ambient temperature:-20 ºC - +50 ºC
Battery charging contact:
Allowable voltage of 17.8 V, Allowable current of 2.72 A
 IP protection class of battery units are IP20.
About combination
Make sure that the product model on the nameplate is correct.
Inappropriate combinations of models deviate from the range of explosion-proof certification.
The nameplate shows the followings as well as the product model.
Product model:
Main unit GX-2012,GX-2012GT
Dry battery unit BUD-2012
Lithium ion battery unit BUL-2012,BUL-2012(G1)
Manufacture:
RIKEN KEIKI Co., LTD.
Explosion-proof grade: Ex ia ⅡC T4 X(GX-2012,GX-2012GT)
Ex ia ⅡC T4(BUD-2012,BUL-2012,BUL-2012(G1))
Ambient temperature: -20 ºC - +50 ºC
Warnings: Inhibit to take off battery unit in non-hazardous area. (GX-2012,GX-2012GT)
Inhibit to take off dry battery in non-hazardous area. (GX-2012,GX-2012GT,BUD-2012)
Powered by three series connected Alkaline AA batteries, type LR6 manufactured by Toshiba.

103 Product Components

3-2. Names and functions for each part3-2. Names and functions for each part
<Outline Drawing> (Main Unit)(11) Gas outlet(2) Buzzer soundopening(12) Holes forhand strap(3) AlarmLEDarrays(10) Gas inlet(3) Alarm LED
arrays(14) Filter case
(1) LCD
display(13) Sensor cover(12) Holes forhand strap(3) AlarmLEDarrays(5) ▲/AIR switch(9) POWER/ENTER switch(7) DISPLAY/ADJ switch(6) ▼/SHIFT switch(8) RESET/SILENCE switch(4) Infraredcommunication
port(15) Battery unit release lever(16) Battery unit connection terminal(1)

LCD display

Displays gas concentrations, alarms, etc.

(2)

Buzzer sound opening

Emits a buzzer sound at an alarm. (Do not block this opening)(3)

Alarm LED arrays

The lamp blinks in response to an alarm.

(4)

Infrared communication port

Used to carry out data communications with a PC in data logger mode.

(5)▲/AIR switch

Used to move from menu to menu in normal order, and to perform the fresh air adjustmentby pressing the switch long, in the display/setting mode.

(6)▼/(SHIFT)switch

Used to move from menu to menu in reverse order in the display/setting mode.

(7)

DISPLAY/ADJ switch

Used to switch to the display/setting mode, etc.

(8)

RESET/SILENCE switch

Used to check and to reset the alarm.

(9)

POWER/ENTER switch

Used to turn on and off the power and to confirm the setting in the display/setting mode.

(10)

Gas inlet

Connecting port for the taper nozzle.

(11)

Gas outlet

Gas outlet, from which gas drawn into the gas monitor is discharged. (Do not block the outlet)(12)

Holes for hand strap (2 positions)

Holes for hand strap. Two holes, one each for right and left.

(13)

Sensor cover

There is a sensor inside. (May be opened only when the sensor is to be replaced)(14)

Filter caseContains a dust filter inside.
(Do not remove the case except for maintenance and replacement)(15)

Battery unit release lever

Lever which is used to remove the battery unit.

(16)

Battery unit connection terminal

Terminal which connects the main unit and the battery unit.

11

3 Product Components

3-2. Names and functions for each part

CAUTION Do not jab the buzzer sound opening with a sharp-pointed item. The unit may malfunction or getdamaged, allowing water or foreign substance, etc. to get inside.
 Do not remove the panel sheet on the surface. The water-proof and dust-proof performances will
be deteriorated.
 Do not affix a label on the infrared communication port. Infrared communications can no longer
be conducted.

<Outline Drawing> (Battery Unit)
Dry battery unit (BUD-2012)
Main unit connection
terminal

Guide

Battery cover fixing leverBattery cover

Lithium ion battery unit: BUL-2012, BUL-8000(G1) (Option)
Main unit connection
terminal

Guide

Charging contacts

12

4 How to Use

4-1. Before using the gas monitor

4

How to Use
4-1. Before using the gas monitor
Not only the first-time users but also the users who have already used the product must follow the operating
precautions. Ignoring the precautions may damage the gas monitor, resulting in inaccurate gas detection.

4-2. Preparation for start-up
CAUTIONThe display is covered by the protective film to prevent scratches from shipping.
Be sure to remove this film before use.
Gas monitor with this film will not satisfy the explosion-proof performance.

Before starting gas detection, check the followings






Check that the protective film attached on the display from shipping is removed.
Check that the battery level is sufficient.
Check that there is no bend or hole in the taper nozzle.
Check that the filter in the main unit is free of dust or clogging.
Check that the main unit and taper nozzle are connected properly.

15

4 How to Use

4-3. Basic operating procedures

4-3. Basic operating procedures<GX-2012>
Normally, the detection mode is used for normal operations. (The detection mode is activated after the
power is turned on.) (* Operations are slightly different depending on the type)<<Detection Mode>>
LCD

RESET/SILENCE

AIR (long pressing)<<Gas Alarm Status>>(Self-latching <Reset after
Recovery to Normal Status>)<<Air Calibration Mode>>

DISPLAY<<Fault Alarm Status>><<Display/Setting Mode>>(Self-latching)19

4 How to Use

4-3. Basic operating procedures<GX-2012GT>
Normally, after the power is turned on, the detection mode (normal mode or leak check mode) is selected
for use.
(* Operations are slightly different depending on the type)<<Mode Selection>>
LCD<<Detection Mode>>(Leak Check Mode)

ENTER<<Detection Mode>>(Normal Mode)RESET/SILENCE

AIR (long pressing)<<Gas Alarm Status>>(Self-latching <Reset after
Recovery to Normal Status>)<<Air Calibration Mode>>

DISPLAY<<Fault Alarm Status>><<Display/Setting Mode>>(Self-latching)

20

ENTER

4 How to Use

4-4. How to start the gas monitor

4-4. How to start the gas monitor<<GX-2012 Start-up Procedure>> (* Operations are slightly different depending on the type)
Keep the POWER switch pressed for three seconds or more.

LCD
All LCDs light up.
Alarm lamp lights up.
Buzzer sounds once (Beep).

Date/Time Display
Example: October 1st, 2012 12:00

Battery voltage display
Example: Voltage 3.3 V* Gas alarm activation
AL-A:
Auto-reset
AL-H:
Self-latching* Types of battery unitD:
Dry battery unit
(No display): Lithium ion battery unit

Gas name display
Example: Gas to be detected CH4, O2, CO, H2S
CH4 Detection range vol%, %LEL

Full Scale Display
Example: CH4 100 %LEL, 100 vol%40.0 %O2
CO
500 ppm
H2S 30.0 ppm

First Alarm Setpoint Display
Example: CH4 10 %LEL
19.5 %
O2
CO
25 ppmH2S 1.0 ppm

Second Alarm Setpoint Display
Example: CH4 50 %LEL
18.0 %
O2
CO
50 ppmH2S 10.0 ppm

21

4 How to Use

4-4. How to start the gas monitor

STEL Alarm Setpoint Display
Example: CO
200 ppm
H2S 5.0 ppm

TWA Alarm Setpoint Display
Example: CO
25 ppmH2S 1.0 ppm

Detection Mode
Buzzer sounds twice (Beep, beep).

CAUTION
After start-up, perform air calibration before performing gas detection. (See '4-7. Air calibration
mode')NOTE A sensor abnormality alarm is issued before the detection mode is entered if there is any abnormality
in the sensor. Press the RESET switch. This will reset the sensor abnormality alarm temporarily, set
the gas concentration display that was abnormal on the sensor to [---], and start gas detection.
However, notify the abnormality to RIKEN KEIKI promptly. Gas for which there was an abnormality inthe sensor cannot be detected. However, the alarm cannot be reset if there is an abnormality in all the
sensors.
 If there is an abnormality in the built-in clock, a fault alarm [FAIL CLOCK] may be issued. Press the
RESET switch. The fault alarm is temporarily reset, and measurement is started with incorrect clock
time.

22

4 How to Use

4-4. How to start the gas monitor<<GX-2012GT Start-up Procedure>> (* Operations are slightly different depending on the type)Press the POWER switch for at least 3 seconds.

LCD
All LCDs light up.
Alarm lamp lights up.
Buzzer sounds once (Beep).

<<Normal Mode>><<Leak Check Mode>>

Mode Selection

ENTER

ENTER

Date/Time Display
Example: October 1st,
2012 12:00

Date/Time Display
Example: October 1st,
2012 12:00

Battery voltage display
Example: Voltage 3.3 V

Battery voltage display
Example: Voltage 3.3 V* Gas alarm activation
AL-A:
Auto-reset
AL-H:
Self-latching* Types of battery unitD:
Dry battery unit
(No display): Lithium ion battery unit

* Gas alarm activation
AL-A:
Auto-reset
AL-H:
Self-latching* Types of battery unitD:
Dry battery unit
(No display): Lithium ion battery unit

Gas name display

Gas name display

Full Scale Display
Example: CH4 100 %LEL,
100 vol%O2
40.0 %
CO
500 ppm

Full Scale Display
Example: CH4 100 %LEL,
100 vol%O2
40.0 %
CO
500 ppm

First Alarm Setpoint Display
Example: CH4 10 %LEL
O2
19.5 %
CO
25 ppm23

4 How to Use

4-4. How to start the gas monitor

Second Alarm Setpoint Display
Example: CH4 50 %LEL
O2
18.0 %
CO
50 ppmSTEL Alarm Setpoint Display
Example: CO
200 ppm

TWA Alarm Setpoint Display
Example: CO
25 ppmDetection Mode <<Normal Mode>>
Buzzer sounds twice (Beep,beep).

Detection Mode <<Leak Check Mode>>
Buzzer sounds twice (Beep,
beep)

CAUTION
After start-up, perform air calibration before performing gas detection. (See '4-7. Air calibration
mode')NOTE A sensor abnormality alarm is issued before the detection mode is entered if there is any abnormality
in the sensor. Press the RESET switch. This will reset the sensor abnormality alarm temporarily, set
the gas concentration display that was abnormal on the sensor to [---], and start gas detection.
However, notify the abnormality to RIKEN KEIKI promptly. Gas for which there was an abnormality inthe sensor cannot be detected. However, the alarm cannot be reset if there is an abnormality in all the
sensors.
 If there is an abnormality in the built-in clock, a fault alarm [FAIL CLOCK] may be issued. Press the
RESET switch. The fault alarm is temporarily reset, and measurement is started with incorrect clock
time.

24

4 How to Use

4-5. How to detect

4-5. How to detect
In each mode, put the taper nozzle close to the detection area and take the reading on the display.
(* Operations are slightly different depending on the type)
GX-2012
GX-2012GT <Normal Mode> Display example
CH4 concentration: 0 %LEL
O2 concentration: 20.9 %CO concentration: 0 ppm
H2S concentration: 0.0 ppm
Time:
12:34
Battery level:
Sufficient

GX-2012GT <Leak Check Mode> Display example
CH4 concentration: 2500 ppm
Battery level:
Sufficient

DANGER While conducting measurement in a manhole or confined space, do not lean over or look into the
manhole or closed space. It may lead to dangers because oxygen-deficient air or other gases
may blow out.
 Oxygen-deficient air or other gases may blow out from the gas exhausting outlet. Never inhale
the air or gases.
 High-concentration (100 %LEL or higher) gases may be discharged. Never use fire near the gas
monitor.

25

4 How to Use

4-5. How to detect

WARNING The gas monitor is designed to draw gases around it under the atmospheric pressure. If
excessive pressure is applied to the gas inlet and outlet (GAS IN, GAS OUT) of the gas monitor,
detected gases may leak out from its inside and may cause dangerous conditions. Avoid
applying excessive pressure to the gas monitor while in use.
 Do not connect the taper nozzle directly to a location with a pressure higher than theatmospheric pressure. The internal piping system may be damaged.
 When the fresh air adjustment is performed in the atmosphere, check the atmosphere forfreshness before beginning the adjustment. If other gases exist, the adjustment cannot be
performed properly, thus leading to dangers when the gas leaks.
 Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.
 Before use, check that there remains sufficient battery power. When the gas monitor is used forthe first time or is not used for a long period, the batteries may be exhausted. Either fully charge
the batteries or replace them with new ones before use.
 If a low battery alarm is triggered, gas detection cannot be conducted. If the alarm is triggered
during use, turn off the power and promptly charge the batteries in a non-hazardous area.
 Do not block the buzzer sound opening. No alarm sound can be heard.

CAUTION When you measure concentrations of oxygen in inert gases for a long time, the carbon dioxide
concentration in the air must be 15 % or less. When you use the gas monitor in the inert gas witha carbon dioxide concentration of 15 % or higher, perform measurement in as short time as
possible. Using the gas monitor under high concentrations for a long time may shorten the life of
the oxygen sensor.
 An oxygen concentration higher than a certain level is required for the combustible gas %LEL
sensor of the gas monitor to correctly detect gases and display concentrations.
 During combustible gas detection (%LEL range), long-time detection of a high-concentration
combustible gas may adversely influence the sensor.

NOTE

 If the combustible gas reading exceeds 100 %LEL, the CO reading rises temporarily but this is notabnormal.
 In a low-temperature environment, the operating time is shortened due to the battery performance
property.
 At a low temperature, the response of the LCD display may get slow down.
 If a combustible gas with a higher concentration than 100 %LEL is drawn, some gas may remain in thetaper nozzle and filter due to adsorption. After drawing a high-concentration combustible gas, clean
the gas monitor to remove the adsorbed gas (draw fresh air and check that the reading becomes zero).
Performing fresh air adjustment before cleaning it completely will result in inaccurate adjustment,
giving adverse influence on measurement.
 Perform gas detection in the vol% range in a place where the presence of a high-concentration
combustible gas is known. (*Only with the types which detect high-concentration combustible gas<vol%>)

26

4 How to Use

4-5. How to detect<Leak Check Mode>(GX-2012GT <Leak Check Mode>)
Depending on the concentration of combustible gas, bar display is increased or decreased and the buzzer
sounds intermittent beeps. As the concentration becomes higher, the interval of intermittent beeps of thebuzzer becomes shorter.
The basic screen transition in the leak check mode is as follows:<<Mode Selection>>
LCD

ENTER

▼(long pressing)<<Leak Check Mode>>

DISPLAY

AIR (long pressing)<<Full Scale Selection>>(1/10，1/5, and 1/2 of F.S., F.S.)<<Air Calibration Mode>>

RESET (long pressing)<<Peak Hold Mode>>

NOTE

Instantaneous The full scale of the leak check can be selected. Every time thevalue
DISPLAY swtich is pressed, the full scale changes between 4
Peak valuelevels: 500 ppm, 1000 ppm, 2000 ppm, and 5000 ppm.
 If the detection result exceeds the full scale, the range changes
Full scale value
automatically to LEL and VOL%.
 The peak of the leak value can be held. Press the RESET switch
long (See the figure on the right).
 The peak value can be cleared by pressing the RESET switch
Peak hold screen(for about 1 second).
 Keep the DISPLAY switch pressed long to turn off the intermittent
beeps of the buzzer at the time of leak check. At this time, [NO ALARM] will be displayed.

27

4 How to Use

4-5. How to detect<Manual Memory> (GX-2012, GX-2012GT <Normal Mode>)
Any instantaneous value during measurement can be recorded.
Up to 256 points of data can be recorded. When the number of recorded data points reaches the maximum,
recorded data will be overwritten, starting from the oldest data.
(1) In the detection mode, press the ▲ switch while the ▼ switch is pressed to prepare the recording. (Forabout one second). The following screens are displayed in turn on the gas monitor.

NOTE
The screen displays the memory number, date, and instantaneous value in turn. Go to the next step toexecute recording. No value is recorded at this point yet. If you do not want to record a value, press the
DISPLAY switch to return to the detection mode.
(2) Press the ENTER switch. The date and the instantaneous value at the time when the ENTER switch ispressed are recorded.
(3) When [SAVED] is displayed and the state returns to (1), the recording is completed.

(4) To continue recording, repeat steps (1) to (3).
To exit the manual memory, press the DISPLAY switch and return to the detection mode.

28

4 How to Use

4-5. How to detect<About Auto Range Switching Point>(GX-2012 TYPE-A, E, GX-2012GT <Normal Mode>(*Only the types which detect high-concentration
combustible gases <vol%>)
If Auto Range is set on a type with the vol% range for combustible gases, the display is automaticallyswitched to the vol% range when the concentration of a detected combustible gas exceeds 100 %LEL.
When the concentration drops, the display returns to the %LEL range again. The following shows anexample of switching timing.
Diagram of gas concentrations and range switching timing under Auto Range setting
CH4 concentration

5 vol%(100 %LEL)
3 vol%(60 %LEL)%LEL range

vol% range

Switching point%LEL range

Switching point

CAUTION
An oxygen concentration higher than a certain level is required for the combustible gas %LEL
sensor of the gas monitor to correctly detect gases and display concentrations. For the sake of moreaccurate gas detection and concentration display, therefore, this gas sensor may perform detection
using the vol% sensor if the built-in oxygen sensor of this gas monitor detects an oxygen
concentration lower than a certain level in the atmosphere.
In other words, the display changes at the timing shown above when the oxygen concentration isequal to or higher than a certain level. If it is lower than a certain level, however, the vol% sensor isused for detection even if the combustible gas concentration is lower than the switching point.

29

4 How to Use

4-6. Modes

4-6. Modes(GX-2012, GX-2012GT <Normal Mode>)

Details on each mode are provided as follows. (* Operations are slightly different depending on the type)
Mode

Item

LCD display

Details

Detection
Mode-

Display

Normal state.

Air Calibration
Mode-[Air CAL]

Perform the zero adjustment.

Display/Setting
Mode

Combustible
Gas
Measurement
Range Setting[HC
RANGE]

Used to select a combustible gas
measurement range manually.

Peak display[PEAK]

Displays the maximum concentration (orminimum concentration for oxygen) detectedduring measurement from power-on to thepresent.

STEL Value
Display[STEL]

Displays the STEL value after power-on.

TWA Value
Display[TWA]

Displays the TWA value after power-on.

Full Scale/
Alarm Setpoint
Display/
Alarm Test

[ALARM-P]

Displays the full scale and alarm setpointvalues and performs the alarm test for thesettings displayed.

Operation Time
Display[OP.TIME]

Displays the operation time.

Date/Time
Display[DATE]

Displays the time based on the built-in clock.

Data Logger
Remaining
Time Display[REMAIN]

Displays the remaining time which data logger
can record.

30

4 How to Use

4-6. Modes

Mode

Item

LCD display

Details

Display/Setting
Mode

Clear Log Data[LG
CLEAR]

Clears the log data.

User ID
Display/
Selection[UId SEL]

Displays and selects the ID.
Displays an ID if it has been set in advance.
Default setting is [----].

Station ID
Display/
Selection[SID SEL]

Displays and selects the ID.
Displays an ID if it has been set in advance.
Default setting is [----].

SnapLog Data
Display[REC.DATA]

Displays data recorded in the manual memory.

Peak Display
ON/OFF
Setting[bAr SEL]

Selects ON (display)/OFF (hide) of the peak
display in the bar graph.

31

4 How to Use

4-7. Air calibration mode

4-7. Air calibration mode
(GX-2012, GX-2012GT) (* Operations are slightly different
depending on the type)Press the AIR switch.

When the AIR switch is pressed, thedisplay changes to [Adj HOLD AIR].

When [RELEASE] is displayed,
release the AIR switch.
The countdown is started (*only withthe types which detect
high-concentration combustible gas<vol%>).
When the zero adjustment is
successfully completed, it returns to
the detection mode.

WARNING
When air calibration is performed in the atmosphere, check the atmosphere for freshness before
beginning the calibration. If other gases exist, the adjustment cannot be performed properly, thus
leading to dangers when the gas leaks.

CAUTION Perform air calibration under pressure and temperature/humidity conditions close to those in theoperating environment and in fresh air.
 Perform air calibration after the reading is stabilized.
 If there is a sudden temperature change of 15 C or more between the storage and operation
locations, turn on the power of the gas monitor, leave the unit for about 10 minutes in a similar
environment to the operation location, and perform air calibration in fresh air before using it.

32

4 How to Use

4-8. Display/setting mode

4-8. Display/setting mode

(GX-2012, GX-2012GT <Normal Mode>)This mode allows you to change various displays and settings.
Every time the DISPLAY switch is pressed, various screens are displayed in turn. (* Operations are slightly
different depending on the type)
LCD
Detection Mode
Press the DISPLAY switch.

Display/Setting Mode
Combustible Gas Measurement
Range Setting
Used to select a combustible
gas measurement range
manually.

ENTER

Combustible Gas Measurement
Range Setting
 P36

ENTER

Full Scale Display/Alarm Setpoint
Display/Alarm Test
 P38

PEAK Value Display
Displays the maximum
concentration (or minimum
concentration for oxygen)detected during measurementfrom power-on to the present.

STEL Value Display
Displays the STEL value after
power-on.

TWA Value Display
Displays the TWA value after
power-on.

Full Scale Display/Alarm
Setpoint Display/Alarm Test
Displays the full scale and alarm
setpoint values and performs thealarm test for the settings
displayed.

34

4 How to Use

4-8. Display/setting mode

Operation Time Display
Displays the operation time.

Date/Time Display
Displays the time based on thebuilt-in clock.

Data Logger Remaining Time
Display
Displays the remaining time
which data logger can record.

Clear Log Data
Clears the log data.

User ID Display/Selection
Displays and selects the ID.

Station ID Display/Selection
Displays and selects the ID.

35

ENTER

Clear Log Data
 P39

ENTER

UID Display/Selection
 P40

ENTER

SID Display/Selection
 P40

4 How to Use

4-8. Display/setting mode

SnapLog Data Display
Displays data recorded in the
manual memory.

Peak Display ON/OFF Setting
Selects ON (display)/OFF (hide)of the peak display in the bar
graph.

ENTER

SnapLog Data Display
 P41

ENTER

Peak Display ON/OFF Setting P42

To Detection Mode

NOTE
The gas monitor automatically returns to the detection mode in about 20 seconds if the gas monitor is left
unoperated.

36

4 How to Use

4-8. Display/setting mode

<Combustible Gas Measurement Range Setting [HC RANGE]>(GX-2012, GX-2012GT <Normal Mode>(*Only the types which detect high-concentration combustible
gases <vol%>)
The type which can display combustible gas levels in two ways, "%LEL range" and "vol% range,"
automatically switch between these two displays according to the gas concentration or oxygen
concentration, from "%LEL range" to "vol% range" and vice versa.
(1) Press the DISPLAY switch and select the combustible gas measurement range setting from thedisplay/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch.

NOTE
If you do not want to make a change, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the measurement range menus, [AUTO RANGE] (automatic
switching) and [ONLY VOL] (fixed to the vol% range) are displayed in turn.
Press the ▲ or ▼ switch to select a measurement range and press the ENTER switch.

(4) When [END] is displayed, the setting is completed.

The display/setting mode menu is displayed again.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

37

4 How to Use

4-8. Display/setting mode

CAUTION No gas alarm is triggered in the combustible gas vol% range-only setting.
In the vol% range-only setting, the screen displays [NO ALARM] because no alarm is triggered.
[NO ALARM] display

vol% range only

NOTE
During vol% range-only measurement, [vol%] and [NO ALARM] displays blink.

38

4 How to Use

4-8. Display/setting mode

<Full Scale Display/Alarm Setpoint Display/Alarm Test [ALARM-P]>(GX-2012, GX-2012GT <Normal Mode>)(*Operations are slightly different depending on the type)
Displays the full scale or alarm setpoint values and performs the alarm test for the settings displayed.
(1) Press the DISPLAY switch and select the full scale display / alarm setpoint display / alarm test from thedisplay/setting mode menu. The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to enter the alarm setpoint or other display.

NOTE
If you do not want to enter any display, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the full scale and alarm setpoint menus, i.e. full scale display,first alarm setpoint display, second alarm setpoint display, STEL alarm setpoint display, and TWA
alarm setpoint display, are displayed in turn.
Press either the ▲ or ▼ switch to select a setting that you want to check.
Select one of the following screens:

Full Scale Display

STEL Alarm Setpoint Display

First Alarm Setpoint Display ([WARNING]) Second Alarm Setpoint Display ([ALARM])

TWA Alarm Setpoint Display(4) Press the ENTER switch to perform alarm test. The alarm operation on this screen can be checked.
Press any switch to stop the alarm operation.
(5) Press the DISPLAY switch to exit the alarm setpoint display or alarm test. The display/setting modemenu is displayed again.
(6) After completion, press the DISPLAY switch to return to the detection mode.

39

4 How to Use

4-8. Display/setting mode

<Clear Log Data [LG CLEAR]> (GX-2012, GX-2012GT <Normal Mode>)
Clears the log data which was recorded.
(1) Press the DISPLAY switch and select the Clear Log Data from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch.
The following screens are displayed in turn on the gas monitor.

NOTE
If you do not want to clear the log data, press the DISPLAY switch to return to the display/setting mode
menu.

(3) Press the ENTER switch.
When [----] display disappears and [END] is displayed, the clear procedure is completed.

(4) Press the DISPLAY switch to return to the display/setting mode menu.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

40

4 How to Use

4-8. Display/setting mode

<User ID Display/Select [UID SEL]> (GX-2012, GX-2012GT <Normal Mode>)<Station ID Display/Select [SID SEL]> (GX-2012, GX-2012GT <Normal Mode>)
Displays and selects the UId (User ID) and the SID (Station ID).
(1) Press the DISPLAY switch and select the ID display/selection from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor. (The figure below is the example ofUser ID display/selection.)(2) Press the ENTER switch to set or select an ID.

NOTE

 If you do not want to set or select an ID, press the DISPLAY switch to return to the display/setting
mode menu.
 When the gas monitor is used for the first time, the ID display indicates [----].
 Unless otherwise specified, IDs of USER-001 to USER-128 (User ID) and 001 to 128 (station ID) areregistered.
 The data logger management program (option) is required to register or change an ID. Please contact
RIKEN KEIKI.
(3) Press either the ▲ or ▼ switch to select an ID.
Every time the ▲ or ▼ switch is pressed, the ID number changes.

(4) Press the ENTER switch.
When [END] is displayed, the setting is completed.

(5) Press the DISPLAY switch to return to the display/setting mode menu.
(6) After completion, press the DISPLAY switch to return to the detection mode.

41

4 How to Use

4-8. Display/setting mode

<SnapLog Data Display [REC.DATA]> (GX-2012, GX-2012GT <Normal Mode>)
Display concentration data recorded to the manual memory.
(1) Press the DISPLAY switch and select the log data display from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to display the log data.

NOTE
If you do not want to display the log data, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, the log data menus are displayed in turn.
Press either the ▲ or ▼ switch to select log data that you want to check. The log data menu displays
the year, month, day, time, and memory number.

(4) Press the ENTER switch to display the selected log data.

(5) If you want to display other log data, press the ENTER switch to return to the log data menu. Repeat
the steps (3) - (5).
(6) After completion, press the DISPLAY switch to return to the detection mode.

42

4 How to Use

4-8. Display/setting mode

<Peak Display ON/OFF Setting [ｂAr SEL]> (GX-2012, GX-2012GT <Normal Mode>)
Selects ON (display)/OFF (hide) of the peak display in the bar graph.
(1) Press the DISPLAY switch and select the Peak ON/OFF setting from the display/setting mode menu.
The following screens are displayed in turn on the gas monitor.

(2) Press the ENTER switch to change the setting.

NOTE
If you do not want to change the setting, press the DISPLAY switch to return to the display/setting modemenu.
(3) Every time the ▲ or ▼ switch is pressed, [On PEAK BAR] (display) and [OFF PEAK BAR]
(non-display) are displayed alternately on the ON/OFF setting menu. Select ON/OFF setting and press
the ENTER switch.

(4) When [END] is displayed, the setting is completed.

The display/setting mode menu is displayed again.
(5) After completion, press the DISPLAY switch several times until it returns to the detection mode.

NOTE
After ON (display) setting is performed, gas concentration will be displayed
as the bar graph level as well as numeric value as shown in the figure on theright.

Peak display

43

4 How to Use

4-9. How to exit

4-9. How to exit
Make the gas monitor draw in fresh air. After the display returns to zero (or 20.9 % for oxygen), keep the
POWER/ENTER switch pressed until the power is turned off.

44

5 Operations and Functions

5-1. Gas alarm activation

5

Operations and Functions
5-1. Gas alarm activation(GX-2012, GX-2012GT <Normal Mode>)

Gas alarm:

Triggered when the concentration of detected gas reaches or exceeds the alarm setpointvalue. <<Self-latching>>
Alarm display: Notifies by blinking of a gas concentration value display, sounding of the buzzer, and lightingof the lamp.
Alarm types: First alarm (WARNING), second alarm (ALARM), OVER alarm, TWA alarm, and STEL alarm(* Operations are slightly different depending on the type)<List of Gas Alarms>
Alarm type
OxygenFirst alarm
19.5 %(Japanspecification)
19.5 %(Exportspecification)
Combustible gas 10 %LEL
Hydrogen
1.0 ppm
sulfide(Japanspecification)
5.0 ppm(Exportspecification)
Carbon25 ppmmonoxide
BuzzerRepeatedlysounds strong
and weakbeeps at about
1 second
intervals.
Beep, beep
Alarm lamp
Repeatedly
blinks at about
1 second
intervals.
LCD display
Gas
concentration
and[WARNING]
display blink.

Second alarm
18.0 %(Japanspecification)
23.5 %(Exportspecification)
50 %LEL
10.0 ppm(Japanspecification)
30.0 ppm(Exportspecification)
50 ppmOVER alarm
40.0 %TWA alarm–

STEL alarm–

100 %LEL
30.0 ppm(Japanspecification)
30.0 ppm(Exportspecification)
500 ppm–
1.0 ppm(Japanspecification)
10.0 ppm(Exportspecification)
25 ppm

–5.0 ppm(Japanspecification)
15.0 ppm(Exportspecification)
200 ppm

Repeatedlysounds strong
and weakbeeps at about
0.5 second
intervals.
Blip, blip
Repeatedly
blinks at about
0.5 second
intervals.
Gas
concentration
and[ALARM]
display blink.

Repeatedlysounds strong
and weakbeeps at about
0.5 second
intervals.
Blip, blip
Repeatedly
blinks at about
0.5 second
intervals.
Gas
concentration
and[OVER] display
blink.

Repeatedlysounds strong
and weakbeeps at about
1 second
intervals.
Beep, beep
Repeatedly
blinks at about
1 second
intervals.
Gas
concentration
and[TWA] display
blink.

Repeatedlysounds strong
and weakbeeps at about
1 second
intervals.
Beep, beep
Repeatedly
blinks at about
1 second
intervals.
Gas
concentration
and[STEL] display
blink.

45

5 Operations and Functions

5-1. Gas alarm activation<Display Operation>
Gas Concentration Display
In a gas alarm, the gas concentration display and the alarm type display
blink.
When the concentration of gas exceeds the detection range (over scale),[∩∩∩] will be displayed on the LCD screen.

Display example
Alarm lamp
The alarm consists of two steps. Each of them is triggered when the respective alarm setpoint value isreached or exceeded.
Buzzer
The alarm consists of two steps. Each of them sounds when the respective alarm setpoint value is reached
to or exceeded.
"Alarm Pattern (H-HH)"

1 second interval

1 second interval
0.5 second interval

RESET

RESET

Secondalarm
Setpoint
First alarm
Setpoint

First alarm
Setpoint
Second alarm
Setpoint

Concentration

Concentration

0.5 second interval"Alarm Pattern (L-LL)"(* oxygen deficiency alarm)

Time

Time

Alarm lamp
BuzzerAlarm lamp
BuzzerWARNING
Issuance of a gas alarm indicates that there are extreme dangers. Take proper actions based onyour judgment.

46

5 Operations and Functions

5-2. Fault alarm activation

5-2. Fault alarm activation
Fault alarm: Triggered when an abnormality is detected in the gas monitor. <<Self-latching>>
Alarm display: Notifies by display of error messages, sounding of the buzzer, and lighting of the lamp.
Alarm types: Low flow rate, sensor abnormality, battery voltage low, system abnormality, and calibration
failureDetermine the causes and take appropriate actions.
If the gas monitor has problems and is repeatedly malfunctioning, contact RIKEN KEIKI immediately.

<Display Operation>
LCD display

Displays an error message.

Alarm lamp

Repeatedly blinks at about one second
intervals.

BuzzerRepeatedly sounds intermittent beeps atabout one second intervals:
Blip, beep, blip, beep

Display example

NOTE

 To reset a low flow rate alarm ([FAIL LOW FLOW]), remove the cause of the low flow rate, and thenpress the RESET switch.
 For information on malfunctions (error messages), see '8. Troubleshooting'.

47

5 Operations and Functions

5-3. Other functions

5-3. Other functions<Calibration History/Various Trend/Event History Functions>(GX-2012, GX-2012GT <Normal Mode>)
The gas monitor has history and trend functions. To use these functions, contact RIKEN KEIKI.

NOTE
The data logger management program (option) is required to use the history and trend functions. Pleasecontact RIKEN KEIKI.
Data logger provides five functions.
(1) Interval trend
Records the change of measured concentration from the time the power is turned ON until the time thepower is turned OFF.
The most latest 100 times worth of measurement data shall be recorded.
When the measurement is conducted more than 100 times, the oldest data will be overwritten by thelatest data.
* However, when the maximum recording time is exceeded, the oldest data will be overwritten even
before the 100th measurement.
The maximum recording time is specified as follows for each interval time.
Interval Time
10 seconds 30 seconds
1 minute
3 minutes
5 minutes 10 minutes
Maximum
10 hours
30 hours
60 hours
180 hours
300 hours
600 hours
Recording Time* The standard interval time is "5 minutes."
Interval time can be set by "Data Logger Management Program" (optional).
(2) Alarm trend
Starting immediately after the alarm is triggered, this function records the change of measured
concentration for one hour, which is from 30 minutes before the alarm was triggered until 30 minutes
after the alarm was triggered.
Alarm trend records the peak value of five-second time at a 5-second interval.
Last eight measurement data shall be recorded.
When the number of data exceeds eight, the oldest data will be overwritten by the latest data.
(3) Alarm event
Records the trigger of alarm as an event.
The event records the time of alarm trigger, the target gas of measurement, and the type of alarm event(AL1, AL2, OVER).
Up to 100 events are recorded, counting backwards from the latest event.
When the number of events exceeds 100, the oldest data will be overwritten by the latest data.
(4) Trouble event
Records the trigger of trouble as an event.
The event records the time when the trouble was triggered, the target gas of measurement, and thetype of fault event.
Up to 100 events are recorded, counting backwards from the latest event.
When the number of events exceeds 100, the oldest data will be overwritten by the latest data.
(5) Calibration history
Records data when the calibration is performed.
The history records the calibration time, concentration value before and after the calibration, as well as
the calibration error.
Up to 100 calibration data are recorded, counting backwards from the latest calibration.
When the calibration is conducted more than 100 times, the oldest data will be overwritten by the latest
data.

48

5 Operations and Functions

5-3. Other functions

NOTE Data logger function of this gas monitor is entirely based on the overwrite system (the oldest data isdeleted and the latest data is recorded).
 The recorded data can be read out by the "Data Logger Management Program" (option). For details,
see Operating Manual 'Data Logger Management Program.'49

6 Maintenance

6-1. Maintenance intervals and items

6

Maintenance
The gas monitor is an important instrument for the purpose of safety.
To maintain the performance of the gas monitor and improve the reliability of safety, perform a regular
maintenance.

6-1. Maintenance intervals and items
 Daily maintenance: Perform maintenance before beginning to work.
 Monthly maintenance: Perform alarm test once a month.
 Regular maintenance: Perform maintenance once or more every six months to maintain theperformance as a safety unit.
Maintenance
item

Daily
maintenance

Monthly
maintenanceRegularmaintenanceCheck that the battery level is sufficient.







Make the gas monitor draw in fresh air. Check thatthe concentration display value is zero (or 20.9
vol% on the oxygen deficiency meter). When thereading is incorrect, perform the zero adjustment(fresh air adjustment) after ensuring that no othergases exist around it.







Checking theoperation of themain unit

See the pilot indicator to check for abnormalities.







Checking theoperation of thepump

See the pump operation status indicator to checkfor abnormalities.







Filter check

Check the dust filter for dust or clogging.







Alarm test

Check the alarm lamp and buzzer for normal
operation using the alarm test function.

-





Span
adjustment

Perform the span adjustment by using thecalibration gas.

-

-



Gas alarm
check

Check the gas alarm by using the calibration gas.

-

-



Battery level
check
Concentration
display check

Maintenance content

50

6 Maintenance

6-2. Gas calibration method<About Maintenance Services> We provide services on regular maintenance including span adjustment, other adjustments andmaintenance.
To make the calibration gas, dedicated tools, such as a gas cylinder of the specified concentration andgas sampling bag must be used.
Our qualified service engineers have expertise and knowledge on the dedicated tools used for services,along with other products. To maintain the safety operation of the gas monitor, please use ourmaintenance service.
 The followings are typical maintenance services. For more information, please contact RIKEN KEIKI.
Main Services
Battery level
check
Concentration
display check
Flow rate check

Filter check
Alarm test
Span adjustment
Gas alarm check: Checks the battery level.
: Verifies that the concentration display value is zero (or 20.9 vol% on the oxygen deficiency
meter) by using the zero gas.
Performs the zero adjustment (fresh air adjustment) if the reading is incorrect.
: Checks the flow rate indicator to find abnormalities.
Checks the flow rate by using an external flow meter to verify the correctness of the flow rate
indicator on the gas monitor. If the flow rate is incorrect, performs the flow rate adjustment.
: Checks the dust filter for dust or clogging.
Replaces a dirty or clogged dust filter.
: Checks the alarm lamp and buzzer for normal operation using the alarm test function.
: Performs the span adjustment by using the calibration gas.
: Checks the gas alarm by using the calibration gas.
 Checks the alarm. (Checks the alarm activation when the alarm setpoint is reached) Checks the delay time. (Checks time to delay until the alarm is triggered) Checks the buzzer, lamp, and concentration display. (Check each activation of ALM1 and
ALM2): Checks dust or damage on surface of the gas monitor, clean and repair such parts of the gas
monitor.
Replaces parts which are cracked or damaged.
: Uses the keys to check the operation of functions and parameters.

Cleaning andrepair of device(visual diagnosis)
Device operation
check
Replacement of: Replaces consumable parts, such as a sensor, filter and pump.
Consumable Parts

6-2. Gas calibration method
Perform span adjustment of sensors using a calibration gas at least once every six months.
Request the dealer or RIKEN KEIKI headquarters or authorized local representative to perform span
adjustment.

CAUTION
Do not use a lighter gas to check the sensitivity of the gas monitor. A constituent of the lighter gas
may deteriorate the sensor performances.

51

6 Maintenance

6-3. How to clean

6-3. How to clean
Clean the gas monitor if it becomes extremely dirty. The gas monitor must be turned off while cleaning it.
Use a waste cloth to remove dust. Do not use water or organic solvent for cleaning because they may cause
malfunctions.
Because an extremely large amount of dust inside the taper nozzle may disturb the gas detection, it must be
cleaned with dry AIR, etc.

CAUTION
When cleaning the gas monitor, do not splash water over it or use organic solvents such as alcoholand benzene on it. The surface of the gas monitor may be discolored or damaged.

NOTE
When the gas monitor gets wet, water may remain in the buzzer sound opening or clearances. Drain
water as follows:(1) Wipe away moisture on the gas monitor thoroughly using a dry towel, cloth, etc.
(2) While holding the gas monitor firmly, shake it about ten times with the buzzer sound opening facing
downward.
(3) Wipe away moisture coming out from the inside thoroughly using a towel, cloth, etc.
(4) Place the gas monitor on a dry towel, cloth, etc. and let it stand at normal temperatures.

6-4. Parts replacement<Replacement of Consumables>
Sensor Replacement
The built-in sensors of the gas monitor have a validity period and must be replaced regularly (within two
years).
The sensor life has expired if, for example, the sensors cannot be calibrated in span adjustment, thereadings do not come back after fresh air adjustment, or the readings fluctuate. Contact RIKEN KEIKI. The
warranty period is one year for all the sensors.
Dust Filter Replacement Procedure
Because the dust filter may gradually get dirty or clogged over the time, it must be replaced regarding theoperating conditions. Check the dust filter, and then replace it as necessary.
Gas inlet partThe gas inlet part contains absorbent cotton, wire mesh filter, and Teflon filter. Replace the filter when it has
absorbed water, has a low flow rate, or looks significantly contaminated.
(1) Turn the filter case counterclockwise and remove it.
(2) Take out the filter and replace with a new filter.

NOTE
The absorbent cotton is installed on the filter case side and the Teflon filter and wire mesh filter are
installed on the main unit side.

52

6 Maintenance

6-4. Parts replacement(3) Attach the filter case that has been removed.

Absorbent
cottonFilter case

Wire mesh
Teflon filter* Belt clip is optional.

Sensor partThe sensor part contains various filters. The filters need to be replaced regularly.
(*Different filters are attached depending on the type)

CAUTION Turn off the power of the gas monitor before replacing the filters.
 Do not remove the cover except for when replacing the filter. When the sensor cover is not
attached properly, accurate measurement may not be possible due to leaks, or water may get
inside.
 Use the dedicated filters for this gas monitor only. Using a similar product may have harmful
effects on the gas detection performance.

(1) Remove the battery unit, loosen the three screws of thesensor cover and remove the sensor cover.

Sensor coverScrew(2) Take out the filters and replace them.
Hydrogen sulfide

Activated carbon filter

Humidity control filter* GX-2012GT does nothave the typewhich contains
humidity control filter.

53

6 Maintenance

6-4. Parts replacement(3) Attach the sensor cover to the main unit and tighten the three screws.

CAUTION
If the screws are not tightened completely, accurate gas measurement may not be possible due toleaks, or water may get inside. The same thing occurs if a minute foreign substance is caught
beneath the knob.

<Replacement of Regular Replacement Parts>
List of recommended regular replacement parts
GX-2012No.

Item

Recommended
maintenanceinterval

Recommended
replacement
interval

Quantity(pieces per
unit)

1

Pump unit (RP-12)

6 months

1 - 2 years

12

H2S sensor filter

3 months

6 months

1

Remarks

Humidity control filter3

CO sensor filter

3 months

6 months

1

Activated carbon filter

4

HC-LEL sensor filter

3 months

6 months1

Hydrogen sulfide
scrubber filter

5

Absorbent cotton–

When dirty

Properquantity

6

Teflon filter

3 months

6 months

1

7

Lithium ion battery unit:(BUL-2012,BUL-2012(G1))–

About 500
cycles ofcharging anddischarging

1

Customers whopurchased lithium ion
battery unit (optional
accessories)

Recommended
maintenanceinterval

Recommended
replacement
interval

Quantity(pieces
per unit)

Remarks

6 months

1 - 2 years

1

GX-2012GT
No.

1

Item

Pump unit (RP-12)

2

CO sensor filter

3 months

6 months

1

Activated carbon filter

3

HC-LEL sensor filter

3 months

6 months1

Hydrogen sulfide scrubber
filter4

Absorbent cotton–

When dirty

Properquantity

5

Teflon filter

3 months

6 months

1

6

Lithium ion battery unit:(BUL-2012,BUL-2012(G1))–

About 500
cycles ofcharging anddischarging

1

Customers whopurchased lithium ion
battery unit (optional
accessories)

NOTE
The above replacement intervals are recommendation only. The intervals may change depending on theoperating conditions. These intervals do not mean the warranty periods either. The result of the regular
maintenance may determine when to replace the parts.
The operation of most of the periodical replacement parts must be checked after replacement by a qualified
service engineer.
For the stable operation of the detector and safety, ask a qualified service engineer to take care of
replacement of the parts whose operation must be checked. Please contact RIKEN KEIKI.

54

7 Storage and Disposal

7-1. Procedures to store the gas monitor or leave it for a long time7

Storage and Disposal
7-1. Procedures to store the gas monitor or leave it fora long time
The gas monitor must be stored under the following environmental conditions.
 In a dark place under the normal temperature and humidity away from direct sunlight In a place where gases, solvents or vapors are not present
Store the gas monitor in a shipping carton, if any, in which the product was delivered.
Store the gas monitor away from dust, etc. if the shipping carton is not available.

CAUTION
If the gas monitor is not used for a long time, turn on the power at least once every six months andcheck that the pump draws in air (about three minutes). The gas monitor, when not activated for along time, may cease to work because of hardening of the grease in the pump motor.

NOTE If the gas monitor with a lithium ion battery unit is not used for a long time, it is recommended to store it
after discharging the batteries until the battery level icon shows one battery mark or so. If the gas
monitor is stored with the batteries fully charged, the batteries get deteriorated more quickly and may
have shorter life.
 If the gas monitor with a dry battery unit is not used for a long time, store it after removing the batteries.
Battery leaks may result in fire or injury. If the gas monitor is not used for a short time, store it without
removing the batteries. While the power of the gas monitor is OFF, the sensor is energized at all times.
Therefore, it is necessary to store the gas monitor with the batteries in it.

7-2. Procedures to use the gas monitor again
CAUTION
When you use a stopped or stored gas monitor again, never fail to perform a gas calibration. For
information on readjustment including gas calibration, please contact RIKEN KEIKI.

55

7 Storage and Disposal

7-3. Disposal of products

7-3. Disposal of products When the gas monitor is disposed of, it must be treated properly as an industrial waste in accordancewith the local regulations.

WARNING Do not disassemble the electrochemical type sensor or galvanic cell type sensor because they
contain electrolyte. Electrolyte may cause severe skin burns if it contacts skin, while it may cause
blindness if it contacts eyes. If electrolyte is adhered on your clothes, that part on your clothes is
discolored or its material is decomposed. If contact occurs, rinse the area immediately with alarge quantity of water.
 Dispose of the batteries or the battery unit in accordance with the procedure specified by the
local authority.
 When disposing of the gas monitor in EU member states, sort the batteries as specified. Handle theremoved batteries according to the classified refuse collection system and recycling system based on
the regulations of EU member states.
Removing batteries
See '4-2. Preparation for start-up' and take out the batteries.
When BUL-2012,BUL-2012(G1) (option) is used
Model
BUL-2012
BUL-2012(G1)Type
Lithium ion battery

NOTE

 BUL-2012,BUL-2012(G1) (option) contains batteries.
 Crossed-out recycle dustbin markThis symbol mark is indicated on the products which contain the batteries which fall under EU Battery
Directive 2006/66/EC. Such batteries need to be disposed of as specified by the latest Directive.
This symbol mark indicates that the batteries need to be separated from the ordinary waste anddisposed of appropriately.

56

8 Troubleshooting

8

Troubleshooting
The troubleshooting does not explain the causes of all the malfunctions which occur on the gas monitor.
This simply helps to find the causes of malfunctions which frequently occur. If the gas monitor shows asymptom which is not explained in this manual, or still has malfunctions even though remedial actions aretaken, please contact RIKEN KEIKI.

<Abnormalities on Unit>
Symptoms

CausesActions

The power cannot
be turned on.

The battery level is too
low.

Dry battery unit: Replace all the three dry batteries with
the new ones in a non-hazardous area.
Lithium ion battery unit: Charge the batteries in a
non-hazardous area.

The power switch was
not pressed longenough.

For power-on, keep the POWER switch pressed until abeep is heard.

Improper installation of
the battery unit

Check whether the battery unit is properly attached to themain unit.

Abnormaloperations

Disturbances bysudden static electricity
noise, etc.

Turn off and restart the gas monitor.

Key operations are
disabled.

Disturbances bysudden static electricity
noise, etc.

In a non-hazardous area, remove the battery unit once,and reinstall the battery unit, and turn on the power toperform operations.

Systemabnormalities[FAIL SYSTEM]

A circuit abnormality
occurred.

Request RIKEN KEIKI for repair.

Systemabnormalities[FAIL SYSTEM]
Abnormalities ofError No. 000 internal ROM
Error No. 010

Abnormalities ofinternal RAM

Request RIKEN KEIKI for repair.

Abnormalities ofError No. 021
internal FRAM
Abnormalities ofError No. 022 internal FLASH
memorySensorabnormalities[FAIL SENSOR]

A sensor has failed.

Request RIKEN KEIKI to replace the sensor.
(Only at power-on, press the RESET switch to continue
the operation using only the normal sensors to detect
other gases.)57

8 Troubleshooting
Symptoms

CausesActions

A low battery
voltage alarm isdisplayed.
[FAIL BATTERY]

The battery level is low.

Dry battery unit: Turn off the power and replace the drybatteries with new ones in a non-hazardous area.

A low flow rate
alarm is displayed.
[FAIL LOW FLOW]

Water or oil, etc. wasdrawn in.

Check the gas sampling hose for any damage or mark ofdrawn water or oil, etc.

The filter is clogged.

Check the attachment, clogging, torsion, etc. of the filter.

The pump hasdeteriorated.

Request RIKEN KEIKI to replace the pump.

The unit was stored fora long time without
being used (6 months
or longer)

When the low flow rate alarm is displayed, turn off the unit
once and then on again. Repeat this procedure several
times. If the problem still persists, request RIKEN KEIKI toreplace the pump.

Lithium ion battery unit: Turn off the power and charge it ina non-hazardous area.

Fresh airadjustment cannot
be performed.
[FAIL AIR CAL]

Fresh air is not supplied Supply fresh air.
around the gas monitor.

Clockabnormalities[FAIL CLOCK]

Abnormalities of theinternal clock

Make a setting of Date/Time.
If such a symptom is observed repeatedly, the built-in
clock is seemingly malfunctioning. Thus, it must be
replaced. Please contact RIKEN KEIKI.

The batteries
cannot berecharged.
(Rechargeable
battery unit only)

The charger is notconnected properly.

Connect the AC plug and DC plug of the AC poweredcharger properly.

A charging circuit
abnormality occurred.

Request RIKEN KEIKI for repair.

The batteries havebeen fully charged.

When fully charged batteries are charged again, thecharging indicator lamp does not go on.

588 Troubleshooting<Abnormalities of Readings>
Symptoms

Causes

The reading rises(drops) and it
remains so.

Drifting of sensor output Perform the zero adjustment.

Actions

Presence ofinterference gas

Disturbances by interference gases, such as solvents,
cannot be eliminated completely.

Slow leakA very small amount of the gas to be detected may beleaking (slow leak). Because ignoring it may cause
dangers, take a remedial measure, i.e., taking actions thesame as those for the gas alarm.

Environmental changes

Perform the zero adjustment.
In particular, the galvanic cell type is affected by the airpressure.

A gas alarm istriggered despite ofno gas leak and noother abnormalities
at the detection
point.

Presence ofinterference gas

Disturbances by interference gases, such as solvents,
cannot be eliminated completely.

Disturbance by noise

Turn off and restart the gas monitor.
If such a symptom is observed frequently, takeappropriate measures to eliminate the noise.

Slow response

Clogged dust filter

Replace the dust filter.

Bended or clogged
taper nozzle

Fix the defective parts.

Condensation is formed Fix the defective parts by providing dry air, etc.
inside the gas monitor.

Span adjustment
impossible

Deteriorated sensor
sensitivity

Replace the sensor with a new one.

Improper calibration
gas concentration

Use the proper calibration gas.

Deteriorated sensor
sensitivity

Replace the sensor with a new one.

59

9 Product Specifications

9-1. List of specifications

9

Product Specifications
9-1. List of specifications
GX-2012 <Japan Ex specifications>
Detection principle

Galvanic cell type (OS)Gas to be detected

Oxygen (O2)

Detection range<Service range>
Display resolution
Alarm setpoint value

0 - 25 vol%<Up to 40 vol%>0.1 vol%
19.5 vol% (L)18.0 vol% (LL)
40.0 vol% (OVER)

Display
Detection method
Flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply

LCD digital (seven-segment + symbol)
Sample-drawing
0.45 L/min or more (Open flow rate)
Clock display, battery level icon, pilot indicator, and pump operation status indicator
95 dB (A) or higher (30 cm)
Lamp blinking, continuous modulating buzzer sounding, gas concentration display blinking, and vibration
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate

Continuous operatingtime
Operating temperature
Operating humidity
Structure
Explosion-proof
structure
Explosion-proof class
Dimension
WeightNew ceramic type (NC)
/Thermal conductivity
type (TE)(*)
Combustible gas(HC/CH4)
0 - 100 %LEL (NC)/Up to 100 vol%(TE)(*)
1 %LEL(NC)/1 vol%(TE)
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)

Electrochemical type
(ES)

Electrochemical type(ES)

Hydrogen sulfide (H2S)

Carbon monoxide (CO)

0 - 30 ppm

0 - 150 ppm<Up to 500 ppm>
1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)

0.1 ppm
1.0 ppm (1st)
10.0 ppm (2nd)1.0 ppm (TWA)
5.0 ppm (STEL)
30.0 ppm (OVER)

Lamp blinking, intermittent buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-2012](Dedicated lithium ion battery unit [BUL-2012,BUL-2012(G1)] can also be used)
BUD-2012: About 15 hours (25 ºC, no alarm, and no lighting)
BUL-2012,BUL-2012(G1): About 10 hours (25 ºC, no alarm, no lighting, and battery fully charged)-20 - +50 ºC
Below 95 %RH (Non-condensing)Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structure
Ex ia ⅡC T4 X (Japan Ex)
Approx. 71 (W)  173 (H)  43 (D) mm (projection portions excluded)
Approx. 360 g (When BUD-2012 is used)/Approx. 360 g (When BUL-2012,BUL-2012(G1) are used)* Specifications subject to changes without notice.
* Detection of high-concentration combustible gases (vol%) is only poss ble with CH4 specification type.

60

9 Product Specifications

9-1. List of specifications

GX-2012 <ATEX/IECEx/UKEX specifications>
Detection principle

Galvanic cell type (OS)New ceramic type (NC)
/Thermal conductivity
type (TE)(*)
Combustible gas(HC/CH4)
0 - 100 %LEL (NC)/Up to 100 vol% (TE)(*)
1 %LEL(NC)/1 vol%(TE)
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)

Gas to be detected

Oxygen (O2)

Detection range<Service range>
Display resolution
Alarm setpoint value

0 - 25 vol%<Up to 40 vol%>0.1 vol%
19.5 vol% (L)23.5 vol% (H)40.0 vol% (OVER)

Display
Detection method
Flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply

LCD digital (seven-segment + symbol)
Sample-drawing
0.45 L/min or more (Open flow rate)
Clock display, battery level icon, pilot indicator, and pump operation status indicator
95 dB (A) or higher (30 cm)
Lamp blinking, continuous modulating buzzer sounding, gas concentration display blinking, and vibration
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate

Electrochemical type
(ES)

Electrochemical type(ES)

Hydrogen sulfide (H2S)

Carbon monoxide (CO)

0 - 30 ppm

0 - 150 ppm<Up to 500 ppm>
1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)

0.1 ppm
5.0 ppm (1st)
30.0 ppm (2nd)10.0 ppm (TWA)
15.0 ppm (STEL)
30.0 ppm (OVER)

Lamp blinking, intermittent buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-2012](Dedicated lithium ion battery unit [BUL-2012,BUL-2012(G1)] can also be used)
BUD-2012: About 15 hours (25 ºC, no alarm, and no lighting)
BUL-2012,BUL-2012(G1): About 10 hours (25 ºC, no alarm, no lighting, and battery fully charged)-20 to +50ºC
Below 95 %RH (Non-condensing)Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structureContinuous operatingtime
Operating temperature
Operating humidity
Structure
Explosion-proof
structure
Explosion-proof class

ATEX/UKEXⅡ1G Ex ia ⅡC T4 Ga (without combustible LEL gas sensor)
Ⅱ1G Ex ia ⅡB T4 Ga (with combustible LEL gas sensor)
IECEx
Ex ia ⅡC T4 Ga (without combustible LEL gas sensor)
Ex ia ⅡB T4 Ga (with combustible LEL gas sensor)
Approx. 71 (W)  173 (H)  43 (D) mm (projection portions excluded)
Approx. 360 g (When BUD-2012 is used)/Approx. 360 g (When BUL-2012,BUL-2012(G1) are used)* Specifications subject to changes without notice.
* Detection of high-concentration combustible gases (vol%) is only poss ble with CH4 specification type.

Dimension
WeightCombination of Detectable Gases by TypeType A

Oxygen (O2)

Combustible gas(HC or CH4)

Combustible gas(CH4)

Hydrogen sulfide(H2S)

Carbon monoxide(CO)0 - 25 vol%<Up to 40 vol%>0 - 100 %LEL

0 - 100 VOL%

0 - 30 ppm

0 - 150 ppm< Up to 500 ppm>








Type B





-





Type C-Type D-Type E









-

-

Type F





-

-

-

61

9 Product Specifications

9-1. List of specifications

GX-2012GT <Japan Ex specifications>
Detection principle

Galvanic cell type (OS)Gas to be detected

Oxygen (O2)

Detection range<Service range>

0 - 25 vol%<Up to 40 vol%>New ceramic type (NC)
/Thermal conductivity
type (TE)(*)
Combustible gas(HC/CH4)
0 - 100 %LEL (NC)/Up to 100 vol%(TE)(*)

Display resolution
Alarm setpoint value

0.1 vol%
19.5 vol% (L)18.0 vol% (LL)
40.0 vol% (OVER)

1 %LEL(NC)/1 vol%(TE)
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)

Display
Detection method
Flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply
Continuous operatingtime

Operating temperature
Operating humidity
Structure
Explosion-proof
structure
Explosion-proof class
Dimension
WeightHot-wire semiconductor
type (SH)Electrochemical type(ES)

Combustible gas(HC/CH4)
0 - 500 ppm (HC)<510 - 2000 ppm>(HC)0 - 2000 ppm(CH4)<2010 - 5000 ppm>(CH4)
10 ppmCarbon monoxide (CO)-0 - 150 ppm<Up to 500 ppm>

1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)LCD digital (seven-segment + symbol + bar display)
Sample-drawing
0.45 L/min or more (Open flow rate)
Clock display, battery level icon, pilot indicator, and pump operation status indicator
95 dB (A) or higher (30 cm)
Lamp blinking, continuous modulating buzzer sounding, gas concentration display blinking, and vibration
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate
Lamp blinking, intermittent buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display, leak check
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-2012](Dedicated lithium ion battery unit [BUL-2012,BUL-2012(G1)] can also be used)
BUD-2012: About 15 hours (25 ºC, no alarm, and no lighting [normal mode])
BUD-2012: About 5.5 hours (25 ºC, no alarm, and no lighting [leak check mode])
BUL-2012,BUL-2012(G1): About 10 hours (25 ºC, no alarm, no lighting, and battery fully charged [normalmode])
BUL-2012,BUL-2012(G1): About 4 hours (25 ºC, no alarm, no lighting, and battery fully charged [leakcheck mode])-20 - +50 ºC
Below 95 %RH (Non-condensing)Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structure
Ex ia ⅡC T4 X (Japan Ex)
Approx. 71 (W)  173 (H)  43 (D) mm (projection portions excluded)
Approx. 360 g (When BUD-2012 is used)/Approx. 360 g (When BUL-2012,BUL-2012(G1) are used)* Specifications subject to changes without notice.
* Detection of high-concentration combustible gases (vol%) is only poss ble with CH4 specification type.

62

9 Product Specifications

9-1. List of specifications

GX-2012GT <ATEX/IECEx/UKEX specifications>
Detection principle

Galvanic cell type (OS)Gas to be detected

Oxygen (O2)

Detection range<Service range>

0 - 25 vol%<Up to 40 vol%>New ceramic type (NC)
/Thermal conductivity
type (TE)(*)
Combustible gas(HC/CH4)
0 - 100 %LEL (NC)/Up to 100 vol%(TE)(*)

Display resolution
Alarm setpoint value

0.1 vol%
19.5 vol% (L)23.5 vol% (H)40.0 vol% (OVER)

1 %LEL(NC)/1 vol%(TE)
10 %LEL (1st)
50 %LEL (2nd)
100 %LEL (OVER)

Display
Detection method
Flow rate
Displays
Buzzer sound volume
Gas alarm display
Gas alarm patternFault alarm/self
diagnosis
Fault alarm display
Fault alarm pattern
Transmission
specifications
FunctionsPower supply

Hot-wire semiconductor
type (SH)Electrochemical type(ES)

Combustible gas(HC/CH4)
0 - 500 ppm(HC)<510 - 2000 ppm>(HC)0 - 2000 ppm(CH4)<2010 - 5000 ppm>(CH4)
10 ppmCarbon monoxide (CO)-0 - 150 ppm<Up to 500 ppm>

1 ppm
25 ppm (1st)
50 ppm (2nd)
25 ppm (TWA)
200 ppm (STEL)
500 ppm (OVER)LCD digital (seven-segment + symbol + bar display)
Sample-drawing
0.45 L/min or more (Open flow rate)
Clock display, battery level icon, pilot indicator, and pump operation status indicator
95 dB (A) or higher (30 cm)
Lamp blinking, continuous modulating buzzer sounding, gas concentration display blinking, and vibration
Self-latching
System abnormalities, sensor abnormalities, battery voltage drop, calibration failure, and low flow rate
Lamp blinking, intermittent buzzer sounding, and detail display
Self-latching
IrDA (for data logger)
LCD backlight, data logger, peak display, log data display, leak check
Dedicated dry battery unit <AA alkaline dry batteries  3> [BUD-2012](Dedicated lithium ion battery unit [BUL-2012,BUL-2012(G1)] can also be used)
BUD-2012: About 15 hours (25 ºC, no alarm, and no lighting [normal mode])
BUD-2012: About 5.5 hours (25 ºC, no alarm, and no lighting [leak check mode])
BUL-2012,BUL-2012(G1): About 10 hours (25 ºC, no alarm, no lighting, and battery fully charged [normalmode])
BUL-2012,BUL-2012(G1): About 4 hours (25 ºC, no alarm, no lighting, and battery fully charged [leakcheck mode])-20 - +50 ºC
Below 95 %RH (Non-condensing)Drip-proof and dust-proof performances (compliant to IP67 level)
Intrinsically safe explosion-proof structureContinuous operatingtime

Operating temperature
Operating humidity
Structure
Explosion-proof
structure
Explosion-proof class

ATEX/UKEXⅡ1G Ex ia ⅡC T4 Ga (without combustible LEL gas sensor)
Ⅱ1G Ex ia ⅡB T4 Ga (with combustible LEL gas sensor)
IECEx
Ex ia ⅡC T4 Ga (without combustible LEL gas sensor)
Ex ia ⅡB T4 Ga (with combustible LEL gas sensor)
Approx. 71 (W)  173 (H)  43 (D) mm (projection portions excluded)
Approx. 360 g (When BUD-2012 is used)/Approx. 360 g (When BUL-2012,BUL-2012(G1) are used)* Specifications subject to changes without notice.
* Detection of high-concentration combustible gases (vol%) is only poss ble with CH4 specification type.

Dimension
WeightCombination of Detectable Gases by Type
Oxygen (O2)

Combustible gas(HC or CH4)

Combustible Combustible gasgas (CH4)(HC or CH4)

Carbon monoxide(CO)0 - 25 vol%<Up to 40 vol%>0 – 100 %LEL

0100 %LEL

0 - 150 ppm<Up to 500 ppm>

0 - 500 ppm (HC)<510 - 2000 ppm>(HC)0 - 2000 ppm (CH4)<2010 - 5000 ppm> (CH4)Type AType B

Type C









-

Type D





-



-

63



9 Product Specifications

9-2. List of accessories

9-2. List of accessories

Standard
accessories








Dry battery unit (BUD-2012)
Alkaline dry batteries: 3
Taper nozzle: 1
Hand strap: 1
Operating manual
Product warranty

Optional
accessories













Float probe
H2S sensor filter (humidity control filter)
Teflon filter
Wire mesh filter
HC-LEL sensor filter (hydrogen sulfide scrubber filter)
CO sensor filter (activated carbon filter)
Charger
Lithium ion battery unit (BUL-2012,BUL-2012(G1))
Silica gel filter
Belt clip
Data logger management program64

10 Definition of Terms

10

Definition of Terms
vol%
ppm
LEL

TWA

STEL

Gas concentration indicated in the unit of one-hundredth of the volume
Gas concentration indicated in the unit of one-millionth of the volume
An abbreviation for "Lower Explosion Limit."
LEL refers to the lowest concentration of a combustible gas in air capable ofcausing explosion when ignited.
An abbreviation for "Threshold Limit Value Time Weighted Average Limit." TWA
refers to a concentration limit of toxic substances as a time weighted average towhich repetitious exposure of almost all the workers in 8-hour work shift or a
40-hour work week does not have harmful effects on their health.
An abbreviation for "Threshold Limit Value Short Term Exposure Limit." STEL
refers to a concentration limit of toxic substances to which everyday exposure ofworkers for 15 continuous minutes lower than TWA does not have harmful
effects on their health.

65