Read and understand this instruction manual before operating
instrument. Improper use of the gas monitor coul d result in bodily
harm or death.
Maintenance of the gas monitor is essential for proper operation and
correct readings.
Bump test the instrument before each day’s use with a known
concentration of each target gas. A bump test can be done in User
Mode’s BUMP TEST item or by applying gas in Measuring Mode. The
instrument does not need to be calibrated unless it does not pass the
User Mode bump test or does not respond appropriately, as defined by
the user, in Measuring Mode. For more information about bump test
and calibration requirements, see IEC 60079-29-2.
This chapter briefly describes the GX-3R Pro gas monitor. This chapter also describes the
GX-3R Pro Operator’s Manual (this document). Table 1 at the end of this chapter lists the
specifications for the GX-3R Pro.
About the GX-3R Pro
Using an advanced detection system consisting of up to four gas sensors, the GX-3R Pro
personal five-gas monitor detects the presence of combustible gas, oxygen (O2), carbon
monoxide (CO), hydrogen sulfide (H2S), and CO2 or a super toxic gas simultaneously. The
GX-3R Pro’s compact size and easy-to-use design make it ideally suited for a wide range of
applications, including sewage treatment plants, utility manholes, tunnels, hazardous waste
sites, power stations, petrochemical refineries, mines, paper mills, drilling rigs, and fire
fighting stations. The GX-3R Pro offers a full range of features, including:
•Simultaneous monitoring of one to five gases
•Liquid crystal display (LCD) for complete and understandable information at a glance
•Ultrabright alarm LEDs
•Distinctive audible/vibrating alarms for dangerous gas conditions and audible alarms for
unit malfunction
•Microprocessor control for reliability, ease of use, and advanced capabilities
•Data logging functions
•Alarm trend data
•STEL, TWA, and over range alarms
•Peak readings
•Built-in time function
•Lunch break feature
•CSA “C/US” classified as intrinsically safe (see Table 4 on page 9)
WARNING:The Model GX-3R Pro detects oxygen deficiency, elevated levels of oxygen,
combustible gases, carbon monoxide, and hydrogen sulfide, all of which
can be dangerous or life threatening. When using the GX-3R Pro, you must
follow the instructions and warnings in this manual to assure proper and
safe operation of the unit and to minimize the risk of personal injury. Be
sure to maintain and periodically calibrate the GX-3R Pro as described in
this manual.
GX-3R Pro Operator’s ManualChapter 1: Introduction • 7
C): ± 5% of reading or ± 2% LEL (whichever is greater)
• Temporary environment (-40°C to -21°C and 51°C to 60°C): ± 10% LEL
Oxygen
± 0.5% O
2
Hydrogen Sulfide
± 5% of reading or ± 2 ppm H
S (whichever is greater)
2
Carbon Monoxide
± 5% of reading or ± 5 ppm CO (whichever is greater)
Carbon Dioxide (IR)
± 5% of reading or ± 2% of full scale (whichever is greater)
HCN, NH
, NO2, PH3, SO2 (EC)
3
± 10% of reading or ± 5% of full scale (whichever is greater)
Indication
Accuracy for
Service
Range
Oxygen
± 3.0% O
2
Hydrogen Sulfide, Carbon Monoxide, and Carbon Dioxide
± 20% of reading
Safety/
Regulatory
• ATEX: Certificate Number: DEKRA 17ATEX0103 X
II1G Ex da ia IIC T4 Ga/IM1 Ex da ia I Ma (with NCR-6309)
II1G Ex ia IIC T4 Ga/IM1 Ex ia I Ma (without NCR-6309)
• IECEx: Certificate Number: IECEx DEK 17.0050X
Ex da ia IIC T4 Ga/Ex da ia I Ma (with NCR-6309)
Ex ia IIC T4 Ga/Ex ia I Ma (without NCR-6309)
• CSA classified, “C/US”, as Intrinsically Safe. Class I Division 1 Groups A, B, C, D T4.
Class I, Zones 0, A/Ex da ia IIC T4 Ga (with NCR-6309)
Class I, Zones 0, A/Ex ia IIC T4 Ga (without NCR-6309)
Alkaline version not verified with CAN/CSA 60079-29-1 & ANSI/ISA 60079-29-1
C US
186718
Power Supply• Lithium ion battery pack (3.7 VDC, 200 mA)
• Single-unit charger (included with Li-ion versions only)
Other
Accessories
Dimensions and
Weigh t
• 12 VDC charger
• Multi-unit charger
• Belt clip
•SDM-3R
•RP-3R
• Aspirator adapter
• IrDA/USB Cable for connecting to a computer when using the Data Logger Management
Program (not needed if computer has an infrared port)
Lithium Ion Battery Pack Version
Approximately 65(H) x 73(W) x 26(D) mm (2.6”H x 2.9”W x 1.0”D)
Approximately 120 g (4.2 oz.)
Alkaline Battery Pack Version
Approximately 65(H) x 73(W) x 34(D) mm (2.6”H x 2.9”W x 1.3”D)
Approximately 140 g (4.9 oz.)
About this Manual
The GX-3R Pro Operator’s Manual uses the following conventions for notes, cautions, and
warnings.
NOTE:Describes additional or critical information.
CAUTION:Describes potential damage to equipment.
WARNING:Describes potential danger that can result in injury or death.
GX-3R Pro Operator’s ManualChapter 1: Introduction • 11
This chapter describes the GX-3R Pro instrument and its accessories.
Instrument Description
Case
The GX-3R Pro’s sturdy, high-impact plastic case is radio frequency (RF) resistant and is
suitable for use in many environmental conditions, indoors and out. The case is dust proof and
water resistant. A clear plastic window on the front of the case allows for LCD viewing. The
black bottom cover, located on the bottom of the case, allows access to the filters and sensors.
A sensor retainer and filter gasket help orient and retain the sensor and filters.
Three threaded inserts on the back of the case allow for installation of an alligator clip or belt
clip.
LCD
A digital LCD (liquid crystal display) is visible through a clear plastic window in the top case.
The LCD simultaneously shows the gas reading for all installed sensors. The LCD also shows
information for each of the GX-3R Pro’s operating modes.
12 • Chapter 2: DescriptionGX-3R Pro Operator’s Manual
Two control buttons, AIR and POWER MODE are located below the LCD.
Table 5: GX-3R Pro Control Button Functions
ButtonFunction(s)
AIR• turns on LCD backlight
• resets alarm condition if LATCHING is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with POWER MODE button
• activates the demand zero function (adjusts the GX-3R Pro’s fresh air
reading)
• changes the value of a parameter available for adjustment
• scrolls through parameter options
POWER MODE• turns the GX-3R Pro on and off
• turns on LCD backlight
• enters and scrolls through Display Mode
• enters instructions into the GX-3R Pro’s microprocessor
• resets alarm condition if LATCHING is set to ON in Maintenance Mode
• enters User Mode, Maintenance Mode, and Gas Select Mode when used
with AIR button
Alarm LEDs
Five sets of red alarm LEDs (light emitting diodes) around the edge of the case alert you to
gas, low battery, and failure alarms.
Buzzer
One solid-state electronic buzzer is located inside the case. Sound exits the case through a
hole in the middle front of the case. The buzzer sounds for gas alarms, malfunctions, low
battery voltage, and as an indicator during use of the GX-3R Pro’s many display and
adjustment options.
Vibrator
A vibrating motor inside the GX-3R Pro case vibrates for gas alarms, unit malfunctions, and
as an indicator during normal use of the various modes of the GX-3R Pro.
NOTE:If STEALTH is set to ON, the vibrator only functions when VIBRATION in the
STEALTH Gas Select Mode item is set to ON. See “Stealth and Vibrator Settings
(STEALTH)” on page 167.
Sensors
The GX-3R Pro uses four sensors to monitor up to 5 gases simultaneously. The sensor retainer
and bottom cover hold the sensors in place. The sensors use different detection principles, as
described below.
Combustible Gas Sensor
The combustible gas sensor detects combustible gas in the % LEL range using 2 catalytic
elements: a standard element and a poison-resistant element that is resistant to sensor poisons
like silicone. The element’s resistance changes based on the reaction of gas with oxygen. The
change in resistance affects the current flowing through the element. The GX-3R Pro’s
circuitry amplifies the current, converts the current to a gas concentration, and displays the
GX-3R Pro Operator’s ManualChapter 2: Description • 13
concentration on the LCD.
The standard calibration for the combustible gas sensor is to methane but the sensor will still
detect and respond to a variety of combustible gases.
O2/CO/H2S/Super Toxic Sensors
The O2, CO, H2S, and super toxic sensors are electrochemical cells that consist of two
precious metal electrodes in a dilute acid electrolyte. A gas permeable membrane covers the
sensor face and allows gas to diffuse into the electrolyte. The gas reacts in the sensor and
produces a current proportional to the concentration of the target gas. The GX-3R Pro’s
circuitry amplifies the current, converts the current to a gas concentration, and displays the
concentration on the LCD.
There are 4 different types of CO and H
S sensors available:
2
•CO only (ESR-A13P-CO): A single electrochemical cell that detects CO.
•H
compensated CO (ESR-A1CP-CO-H): A single electrochemical cell that detects CO.
2
This sensor does not respond to or responds minimally to hydrogen (displays H2 RICH
once H2 concentration reaches 2000 ppm).
•H
•CO/H
S only (ESR-A13i-H2S): A single electrochemical cell that detects H2S.
2
S (ESR-A1DR-COHS): A combination electrochemical cell that detects both CO
2
and H
S.
2
IR Sensors
The infrared sensors detect CO
in the ppm and %volume ranges. Gas enters the sensor
2
through an opening on its face. Infrared light shines through the gas and into an infrared
detector. The intensity of the infrared light changes with the gas concentration and this change
is converted to an electrical signal. The GX-3R Pro’s circuitry converts the signal into a gas
concentration and displays the gas concentration on the LCD.
Dummy Sensors
A dummy sensor is installed in any units that have less than 4 sensors. Dummy sensors are
factory installed. The flat side of the dummy sensor faces away from the GX-3R Pro and the
hollow side faces toward the GX-3R Pro.
Filters
Combustible Gas Sensor H2S Removal Filter Disk (Dark Red)
An H2S removal filter disk is placed into a recess in the filter gasket over the combustible gas
sensor. The filter disk prolongs the life of the combustible gas sensor by preventing H
ambient air from reaching the sensor. The H2S filter disk is dark red in color and although it
may darken over time, its color is not indicative of remaining filter life.
The H2S filter disk needs replacing once it’s been exposed to 33 ppm hours of H2S. This
means the filter needs replacing after 80 minutes of exposure to 25 ppm H2S which equates to
40 2-minute calibrations with a cylinder containing 25 ppm H2S. If H2S exists in the
monitoring environment, the H2S filter disk will have to be replaced more frequently.
S in the
2
CO/H2S Sensor Dual Filter (Black and White)
A dual filter is placed into a recess in the filter gasket over the dual CO/H2S sensor. The black
half is a charcoal filter for the CO sensor. The white half is a humidity filter for the H
S
2
sensor.
Replace the filter if you notice:
•Unexplained CO readings.
•For users with a 1 ppm H2S alarm setpoint: A drift on the H2S zero reading,
14 • Chapter 2: DescriptionGX-3R Pro Operator’s Manual
unexplained H2S readings, the filter appears dirty, or every 6 months (whichever is
sooner).
CO Sensor Charcoal Filter (Black)
A black charcoal filter is placed into a recess in the filter gasket over the CO sensor. The
charcoal filter disk scrubs H2S and certain hydrocarbons out of the sample to avoid false CO
readings. If false or elevated CO readings are noticed, especially in the presence of H2S,
change the charcoal filter.
H2S and PH3 Sensors’ Humidity Filter (White)
A white humidity filter is placed into a recess in the filter gasket over the H
(if an H
S or PH3 sensor is installed). The filter absorbs humidity in the sampling
2
S or PH3 sensor
2
environment to prevent unstable readings around 0 ppm. “H2S” and “PH3” are printed on the
side of the filter.
•H2S: For users with a 1 ppm H2S alarm setpoint, the filter should be replaced every 6
months, if you notice a drift on the zero reading, or if the filter appears dirty
(whichever is sooner). For users with a 2 ppm or higher H2S alarm setpoint, the filter
does not necessarily ever need to be replaced.
•PH3: The filter should be replaced every 6 months.
NO2 and SO2 Sensors’ H2S Removal Filter Disk (Tan)
An H2S removal filter disk is placed into a recess in the filter gasket over the NO2 or SO2
sensor (if an NO2 or SO2 sensor is installed). The filter disk prolongs the life of the sensors by
preventing H2S in the ambient air from reaching the sensor. The filter should be replaced
every 6 months.
HCN Sensor’s H2S Removal Filter Disk (Dark Gray)
An H2S removal filter disk is placed into a recess in the filter gasket over the HCN sensor (if
an HCN sensor is installed). The filter disk prolongs the life of the sensors by preventing H2S
in the ambient air from reaching the sensor. The filter should be replaced every 6 months.
NH3 Sensor’s Humidity Filter (White)
A white humidity filter is placed into a recess in the filter gasket over the NH3 sensor (if an
NH3 sensor is installed). The filter absorbs humidity in the sampling environment to prevent
unstable readings around 0 ppm. The filter should be replaced every 6 months. “NH3” is
printed on the side of the filter.
Hydrophobic Dust Filter
The oval-shaped hydrophobic dust filter is attached to the top of the filter gasket, covering the
sensor ports and the filters. The filter gasket and hydrophobic dust filter get replaced as a set.
NOTE:Some GX-3R Pros have a hydrophobic dust filter that is not attached to the filter
gasket. When replacing the hydrophobic dust filter on one of these GX-3R Pros,
remove the filter and
the gasket and replace it with a filter gasket/hydrophobic dust
filter assembly.
Infrared Communications Port
An infrared (IR) communications port is located on the top of the case, near the top LEDs.
Logged data transmits through the port in standard IrDA protocol. A computer’s infrared port
or an IrDA/USB cable connected to a USB port can be used to download data to the GX-3R
Data Logger Management Program. See the GX-3R Data Logger Management Program
operator’s manual for data logging and downloading instructions.
GX-3R Pro Operator’s ManualChapter 2: Description • 15
The GX-3R Pro is either powered by a rechargeable lithium-ion (Li-ion) battery pack or an
alkaline battery pack with 2 AAA batteries (Duracell MN2400 or PC2400). Instruments with
a Li-ion battery pack have a charging socket on the back of the instrument. Instruments with
an alkaline battery pack have a cover that allows for battery replacement.
The battery icon in the upper right of the LCD shows remaining battery life. A low battery
warning activates when the GX-3R Pro detects a low battery voltage. The GX-3R Pro sounds
a dead battery alarm when battery voltage is too low for Measuring Mode.
NOTE:Use of batteries or battery chargers not specified by RKI Instruments, Inc. will
compromise the CSA classification and may void the warranty. See pg.100 and
pg.102 for more information.
WARNING:To prevent ignition of a hazardous atmosphere, batteries must only be
changed or charged in an area known to be nonhazardous.
AVERTISSEMENT:Pour éviter l’inflammation d’une atmosphère dangereuse, les batteries
doivent uniquement être modifiés ou facturés dans une zone connue
comme non dangereuse.
Included Accessories
Alligator Clip
An alligator clip is installed on the back of the GX-3R Pro. The alligator clip can be used to
attach the GX-3R Pro to clothing or a belt. Teeth in the alligator clip’s jaws prevent the unit
from slipping off. The alligator clip can be rotated to change the instrument’s orientation.
Rubber Boot
A black rubber boot is installed on the GX-3R Pro.
Wrist Strap
A wrist strap is included with the GX-3R Pro and can be attached to the wrist strap installation
feature on the left side of the GX-3R Pro’s case.
16 • Chapter 2: DescriptionGX-3R Pro Operator’s Manual
The charging cable is a 4 foot cable with an AC adapter on one end and a charging plug that
connects to the GX-3R Pro on the other end.
Calibration Cup
Use the calibration cup to apply gas during a bump test, calibration, or gas test. The
calibration cup has an installation orientation to observe. “Front” and “rear” imprinting on the
bottom of the cup correspond to the front and rear of the GX-3R Pro when the calibration cup
is installed. In addition, a “front” label on the front of the calibration cup should be visible
when viewing the LCD with the calibration cup installed.
Other Accessories
12 VDC Charger
The 12 VDC charger is a 4 foot cable with a vehicle plug on one end and a plug that connects
to the GX-3R’s power jack on the other end.
Multi-Unit Charger
The multi-unit charger is a 4 foot wall plug style adapter that plugs into a bar. The bar has five
2-foot cables coming out one side. The end of each of the five cables has a plug that connects
to the GX-3R Pro’s power jack. The AC adapter is rated 100 - 240 VAC input, 5.99 VDC
output.
GX-3R Pro Operator’s ManualChapter 2: Description • 17
A belt clip makes it easy to hook the GX-3R Pro to a utility belt.
SDM-3R
The SDM-3R is a calibration station for the GX-3R and GX-3R Pro. The station’s buttons can
be used for operations (Standalone Mode) or a computer can be used to control the docking
station (PC Controlled Mode). See the appropriate SDM-3R manual for more information.
RP-3R
The RP-3R is a pump that draws sample to the GX-3R Pro. See the RP-3R manual for more
information.
Aspirator Adapter
The aspirator adapter is a squeeze-bulb assembly that draws sample to the GX-3R Pro.
IrDA Cable
Unless your computer has a built-in IrDA port, an IrDA cable is needed to establish
communication between the GX-3R Pro and the Datalogging Program.
18 • Chapter 2: DescriptionGX-3R Pro Operator’s Manual
This chapter explains how to perform confined space entry monitoring or general area
monitoring in the GX-3R Pro’s Measuring Mode.
Start Up
This section explains how to start up the GX-3R Pro, get it ready for operation, and turn it off.
NOTE:The screens illustrated in this section are for a 4-gas + 0 - 10.00% volume CO2 unit.
The screens displayed by your GX-3R Pro may be slightly different.
Turning On the GX-3R Pro
To illustrate certain functions, the following description of the GX-3R Pro start up sequence
assumes that the following menu items are turned on: LUNCH BREAK, CAL REMINDER,
and BUMP REMINDER in User Mode, and ID DISPLAY and AUTO ZERO in
Maintenance Mode. If any of these items are turned off, then the corresponding screens will
not appear.
1 .Press and briefly hold down POWER MODE. Confirm that the LCD turns on, the LEDs
flash, the buzzer sounds, and the motor vibrates before continuing with operation.
Release the POWER MODE button when you hear a beep.
2 .If LUNCH BREAK is set to ON (factory setting is OFF, see pg.88), the Lunch Break
Screen appears. The unit counts down from 5 seconds.
a. Continue Accumulating
(TWA) readings from the last time the GX-3R Pro was used, press and release
POWER MODE or allow the countdown to reach 0. The short-term exposure limit
(STEL) reading is reset each time the GX-3R Pro is turned on.
b. Reset Accumulation
(TWA) readings, press and release AIR before the countdown reaches 0.
GX-3R Pro Operator’s ManualChapter 3: Operation • 19
: To continue accumulating peak and time-weighted average
: To reset the accumulation of peak and time-weighted average
3 .If CAL REMINDER is set to ON (factory setting) and a calibration is due, the screen
7:49
CONFIRM TO USE
USER MODE:MODE
NO :AIR
CAL DATE PAST
7:49
CANNOT USE
USER MODE:MODE
CAL DATE PAST
7:49
NO EFFECT
USER MODE:MODE
CAL DATE PAST
that appears next depends on how CAL EXPIRED is set in User Mode (see pg.76). The
three possible screens are described below. If a calibration is not due, the instrument
displays the number of days left until a calibration is due.
and release POWER MODE to
perform a calibration. The instrument
takes you straight to the AUTO CAL
CYLINDER A screen in User Mode’s
GAS CAL\AUTO CAL item. See
pg.62 for calibration instructions.
If the calibration is successful, the
screen above will not appear again
until the unit is due for calibration. If
the calibration is not successful, the
screen above will again appear in the
startup sequence.
• Option B, Bypass message
continue without performing a
calibration, press and release AIR.
: To
: Press
The GX-3R Pro cannot be used until a
successful calibration is performed.
Press and release POWER MODE to
perform a calibration. The instrument
takes you straight to the AUTO CAL
CYLINDER A screen in User Mode’s
GAS CAL\AUTO CAL item. If you
don’t press POWER MODE, the instru-
ment automatically goes to the AUTO
CAL CYLINDER A screen after 6 seconds. See pg.62 for calibration instruc-
tions.
If the calibration is successful, the
screen above will not appear again until
the unit is due for calibration. If the cali-
bration is not successful, the screen
above will again appear in the startup
sequence.
CAL EXPIRED set to
CANNOT USE
• Option A, Perform calibration
perform a calibration, press and
release POWER MODE. The
instrument takes you straight to the
AUTO CAL CYLINDER A screen in
User Mode’s GAS CAL\AUTO CAL
item.
• Option B, Bypass message
continue without performing a
calibration, wait a few seconds for the
instrument to continue with its startup
sequence.
20 • Chapter 3: OperationGX-3R Pro Operator’s Manual
www.GlobalTestSupply.com
4 .If BUMP REMINDER is set to ON (factory setting is OFF) and a bump test is due, the
7:49
CONFIRM TO USE
USER MODE:MODE
NO :AIR
BUMP DATE PAST
7:49
CANNOT USE
USER MODE:MODE
BUMP DATE PAST
7:49
NO EFFECT
USER MODE:MODE
BUMP DATE PAST
7:49
MM/DD/YYYY
1/14/2019
7:49
DATE
screen that appears next depends on how BUMP EXPIRED is set in User Mode (see
pg.81). The three possible screens are described below. If a bump test is not due, the
instrument displays the number of days left until a bump test is due.
and release POWER MODE to
perform a bump test. The instrument
takes you straight to the BUMP TEST
CYLINDER A screen in the BUMP
TEST User Mode item. See pg.56 for
bump test instructions.
If the bump test is successful, the
screen above will not appear again
until the unit is due for bump testing.
If the bump test is not successful, the
screen above will again appear in the
startup sequence.
• Option B, Bypass message
continue without performing a bump
test, press and release AIR.
: To
: Press
The GX-3R Pro cannot be used until a
successful bump test is performed. Press
and release POWER MODE to perform a
bump test. The instrument takes you
straight to the BUMP TEST CYLINDER
A screen in the BUMP TEST User Mode
item. If you don’t press POWER MODE,
the instrument automatically goes to the
BUMP TEST CYLINDER A screen after
6 seconds. See pg.56 for bump test
instructions.
If the bump test is successful, the screen
above will not appear again until the unit
is due for bump testing. If the bump test
is not successful, the screen above will
again appear in the startup sequence.
BUMP EXPIRED set to
CANNOT USE
• Option A, Perform bump test
perform a bump test, press and release
POWER MODE. The instrument
takes you straight to the BUMP TEST
CYLINDER A screen in the BUMP
TEST User Mode item.
• Option B, Bypass message
continue without performing a bump
test, wait a few seconds for the
instrument to continue with its startup
sequence.
BUMP EXPIRED set to
NO EFFECT
: To
: To
5 .The Date/Time Screen appears for a few seconds.
GX-3R Pro Operator’s ManualChapter 3: Operation • 21
www.GlobalTestSupply.com
6 .The Battery Voltage Screen appears for a few seconds. The battery voltage is on the top
7:49
3.7V
LATCHING
Li-ion
FULL SCALE
7:49
40.0 10.00
O2 % CO2 vol%
100 2000 200.0
CH4 %LEL CO ppm H2S ppm
WARNING
7:49
19.5 0.50
O2 % CO2 vol%
10 25 5.0
CH4 %LEL CO ppm H2S ppm
ALARM
7:49
18.0 3.00
O2 % CO2 vol%
25 50 30.0
CH4 %LEL CO ppm H2S ppm
ALARM H
7:49
23.5 3.00
O2 % CO2 vol%
50 1200 100.0
CH4 %LEL CO ppm H2S ppm
STEL
7:49
3.00
CO2 vol%
200 5.0
CO ppm H2S ppm
TWA
7:49
0.50
CO2 vol%
25 1.0
CO ppm H2S ppm
GAS NAME
7:49
O2 CO2
O2 % CO2 vol%
CH4 CO H2S
CH4 %LEL CO ppm H2S ppm
line. The alarm latching/self-resetting setting is on the second line (see pg.154 for a
description of how to change this setting). The battery pack type is on the bottom line.
7 .The following screens display for 3 seconds each: the Gas Name Screen, the Full Scale
Screen, the Warning Setpoint Screen, the Alarm Setpoint Screen, the Alarm H Setpoint
Screen, the STEL Alarm Screen, and the TWA Alarm Screen.
NOTE:If the combustible gas is set to something other than CH4 or H2 in Gas Select
Mode, the combustible channel is displayed as “HC” and the gas formula for the
combustible gas sensor’s target gas appears during startup.
22 • Chapter 3: OperationGX-3R Pro Operator’s Manual
8 .If ID DISPLAY is set to ON (factory setting is OFF, see pg.155), the User ID Screen
7:49
USER_ID_
001
USER ID
7:49
STATION_
ID_001
STATION ID
7:49
FAIL
CH4 %LEL
FAIL SENSOR
7:49
YES : MODE
NO : AIR
AUTO ZERO
appears for a few seconds, followed by the Station ID Screen.
9 .If the GX-3R Pro experiences a sensor failure during start up, the display shows which
sensor failed and the buzzer sounds a double pulsing tone once per second. In the
example below, the combustible gas sensor failed.
Press and release POWER MODE to acknowledge the failure and continue. “- - - -”
replaces the failed sensor’s gas reading. Replace the failed sensor as soon as possible.
10 . If AUTOZERO is set to ON (factory setting is OFF, see pg.155), the instrument
prompts you to do an auto zero.
WARNING:Make sure that the instrument is in a known fresh air environment (an
environment free of combustible or toxic gases and of normal oxygen
content, 20.9%) before performing an auto zero operation. If you perform
an auto zero operation in an area with gases present, the adjustment will
not be accurate.
a. An auto zero operation sets the combustible gas, H2S, CO, and super toxic channels
to 0 and the OXY channel to 20.9%.
b. If the instrument has a CO2 sensor installed and if CO2AIR SETTING is set to ON
in User Mode, the CO2 channel gets set to 400 ppm (0.04% volume) during an auto
zero. If CO2AIR SETTING is set to OFF in User Mode, the CO2 channel is not
adjusted during the auto zero.
c. You must press and release POWER MODE to perform an auto zero function. If you
do not press any key, after 15 seconds, the instrument enters Measuring Mode
without performing an auto zero.
GX-3R Pro Operator’s ManualChapter 3: Operation • 23
11 . The combustible gas sensor actually contains 2 separate sensors: a standard catalytic
7:49
LIMITED
HC GAS LIST
7:49
20.9 0.00
O2 % CO2 vol%
0 0 0.0
CH4 %LEL CO ppm H2S ppm
sensor and a backup, poison-resistant sensor that is resistant to sensor poisons like
silicone. A LIMITED HC GAS LIST alarm indicates that the standard sensor has a
reduced output, possibly due to one or more sensor poisons in the environment, and that
the poison-resistant sensor is being used to provide gas readings. The poison-resistant
sensor has a limited list of detectable gases. The table shown on pg.40 shows which
gases can and cannot be detected after receiving a LIMITED HC GAS LIST alarm.
If your application requires detection of a gas still detectable after a LIMITED HC GAS
LIST alarm (like methane or isobutane), there is no need to replace the combustible gas
sensor.
However, if your application requires detection of a gas not detectable after a LIMITED
HC GAS LIST alarm (like methanol or ethanol), you must replace the combustible gas
sensor as soon as possible.
The following screen displays, the LEDs flash, and the instrument beeps.
Press and release POWER MODE to confirm the limited gas list and continue to
Measuring Mode.
12 . At the end of the 45 second warmup, the GX-3R Pro begins monitoring for gas in
Measuring Mode. The Measuring Mode Screen displays the current gas reading for each
target gas.
Performing a Demand Zero
Perform a demand zero before using the GX-3R Pro. A demand zero operation sets the
combustible gas, H
If the instrument has a CO2 sensor installed and if CO2AIR SETTING is set to ON in User
Mode, the CO2 channel gets set to 400 ppm (0.04% volume). If CO2AIR SETTING is set to
OFF in User Mode, the CO2 channel is not adjusted during the demand zero.
1 .Find a fresh-air environment. This is an environment free of toxic or combustible gases
and of normal oxygen content (20.9%).
2 .Turn on the unit as described above in “Turning On the GX-3R Pro”.
3 .Press and hold AIR. The LCD prompts you to continue holding AIR and the buzzer
pulses while you hold the button (if KEY TONE is set to ON in User Mode).
4 .Continue to hold AIR until the LCD prompts you to release it. The GX-3R Pro sets the
fresh air readings for all channels. Start up is complete and the unit is now ready for
monitoring.
S, CO, and super toxic channels to zero and the OXY channel to 20.9%.
2
24 • Chapter 3: OperationGX-3R Pro Operator’s Manual
1 .Press and hold POWER MODE.
2 .TURN OFF appears on the display and the buzzer pulses for about five seconds (if KEY
TONE is set to ON in User Mode).
3 .Release the button when TURN OFF disappears from the display.
4 .If you plan to leave the instrument off for an extended period of time, see pg.112.
Measuring Mode Operation
When the GX-3R Pro completes its startup sequence, it is in Measuring Mode. In Measuring
Mode the GX-3R Pro continuously monitors the sampled atmosphere and displays the target
gas concentrations. The GX-3R Pro is considered to be in Normal Operation if there are no
alarm indications.
Heart Symbol: The heart symbol in the upper left corner of the LCD indicates the operation
status and blinks when normal. A microprocessor error causes the heart symbol to stop
flashing or to disappear.
Check Mark: If BUMP REMINDER is set to ON and if a bump test is not due, a check mark
appears in the upper left corner of the LCD.
“S”: If the instrument is operating in Stealth Mode, an “S” appears at the top of the LCD.
Buzzer Icon: The buzzer icon indicates the buzzer volume. Lines in front of the icon indicate a
high buzzer volume. No lines in front of the icon indicates a low buzzer volume.
Bluetooth Icon: The Bluetooth icon flashes when the instrument is trying to pair to a phone.
The Bluetooth icon is steadily on when the instrument is paired to a phone. The Bluetooth
icon is off when the instrument is not paired and is not trying to pair to a phone.
Backlight: In a low-light environment, press and release either button to turn on the display
backlight. See pg.91 to set the backlight time.
Confirmation/Non-Compliance Indicator: If the BEEP menu item in User Mode is set to
anything other than OFF, the GX-3R Pro gives periodic indications to confirm that it’s
operating or to indicate a non-compliance (see pg.89 for instructions).
Monitoring an Area
1 .Start up the GX-3R Pro as described above in “Start Up” on page 19. It is now in
Measuring Mode.
2 .Take the GX-3R Pro to the monitoring area.
3 .Wait at least 15 seconds and observe the display for gas readings. If a reading is
observed, allow the reading to stabilize to determine the gas concentration(s) present.
If you are sampling with an aspirator adapter, see pg.29.
GX-3R Pro Operator’s ManualChapter 3: Operation • 25
4 .If a gas alarm occurs, take appropriate action. See pg.32.
5 .Do not expose the GX-3R Pro to rain.
6 .The GX-3R Pro’s IP 66/68 ratings do not imply that the GX-3R Pro will detect gas
during and after exposure to those conditions. If exposure occurs, dry the instrument
with a cloth and perform a bump test as described on pg.56.
7 .If the GX-3R Pro gets exposed to flammable liquids:
a. Wipe the instrument off with a cloth dampened with water.
b. Replace the filters as described on pg.104 and pg.106 if they became saturated
c. Perform a bump test as described on pg.56.
8 .If you suspect that the GX-3R Pro is not operating correctly:
a. Take the GX-3R Pro to a fresh air environment and perform a demand zero as
described on pg.24.
b. Perform a bump test as described on pg.56.
Combustible Gas Detection
There are three issues to keep in mind when monitoring for combustible gas.
Response
The combustible gas sensor responds to any combustible gas. The standard calibrated target
gas for the combustible gas channel is methane (CH
calibrated to a different combustible gas, such as hexane or propane, the gas name right above
the readings displays as “HC”.
Automatic Conversion
). If the instrument is setup for and
4
The GX-3R Pro can automatically display converted target gas readings if the instrument’s
calibrated target gas is methane or isobutane. See “Combustible Sensor Target Gas
Conversion (HC GAS LIST)” on page 40.
Manual Conversion
You can manually calculate a converted target gas reading using Table 6 below if the
instrument’s calibrated target gas is methane. The table below lists the conversion factors for
several hydrocarbon gases if the GX-3R Pro is calibrated to methane.
To use this table, multiply the display reading on the combustible gas channel by the factor in
the appropriate row to obtain the actual gas concentration. For example, if you are detecting
ethylene and the display reads 10% LEL for the combustible gas channel, you actually have
10% LEL x 0.83 = 8.3% LEL ethylene present.
Table 6: LEL Hydrocarbon Conversion Factors
Gas
Acetone2.22IPA1.64
Acetylene1.43Isobutane1.10
Benzene2.50MEK2.63
Butadiene1.52Methane1.00
LEL Conversion Factor
(from CH
Cal.)
4
Gas
LEL Conversion Factor
(from CH4 Cal.)
Cyclopentane1.45Methanol1.82
DME1.16MIBK4.00
Ethane0.94MMA3.33
26 • Chapter 3: OperationGX-3R Pro Operator’s Manual
The GX-3R Pro protects the combustible gas sensor by temporarily turning off the sensor
power if levels exceeding 100% LEL are detected. Nevertheless, combustible gas
concentrations above 100% LEL can still affect the zero level or calibration of the
combustible gas sensor.
CAUTION:Do not expose the combustible gas sensor to high concentrations of
combustible gas such as that from a butane lighter. Exposure to high
concentrations of combustible gas may adversely affect the performance of the
sensor.
CAUTION:Any rapid increase in the combustible gas reading on the combustible gas
channel followed by a declining or erratic reading may indicate a gas
concentration above the LEL which may be hazardous.
Damaging Gases
Some gases such as silicone vapors, chlorinated hydrocarbons, and sulphur compounds can
contaminate the sensor’s detection elements. This causes sensor damage and/or a reduced
response to combustible gas. Make every effort to avoid these gases.
The H2S scrubber disks protect the combustible sensor from H2S, but you should avoid other
sulphur compounds.
LIMITED HC GAS LIST Alarm
An HC GAS LIST LIMITED alarm can occur at startup or after a calibration.
The combustible gas sensor actually contains 2 separate sensors: a standard catalytic sensor
and a backup, poison-resistant sensor that is resistant to sensor poisons like silicone. A
LIMITED HC GAS LIST alarm indicates that the standard sensor has a reduced output,
possibly due to one or more sensor poisons in the environment, and that the poison-resistant
sensor is being used to provide gas readings. The poison-resistant sensor has a limited list of
detectable gases. The table shown on pg.40 shows which gases can and cannot be detected
after receiving a LIMITED HC GAS LIST alarm.
If your application requires detection of a gas still detectable after a LIMITED HC GAS LIST
alarm (like methane or isobutane), there is no need to replace the combustible gas sensor
.
However, if your application requires detection of a gas not detectable after a LIMITED HC
GAS LIST alarm (like methanol or ethanol), you must replace the combustible gas sensor as
soon as possible.
GX-3R Pro Operator’s ManualChapter 3: Operation • 27
The aspirator adapter accessory is used when it is necessary to draw sample from an area that
cannot be entered or that must be checked for safety before entry, such as a tank or confined
space.
NOTE:The CSA combustible performance certification for the GX-3R Pro does not
include the aspirator adapter.
1 .Turn on the GX-3R Pro as described on pg.19.
2 .Attach the sample cup to the GX-3R Pro. Use the label and imprinting to make sure that
the sample cup gets installed in the correct orientation relative to the GX-3R Pro. Be sure
the sample cup is pushed on all the way.
3 .Screw the probe onto the threaded end of the hose.
4 .Attached the hose and probe to the aspirator bulb.
5 .Insert the end of the probe into the area to be sampled.
6 .Squeeze and release the aspirator bulb 15 times.
7 .Monitor the readings and note if any alarms occur. The readings will peak shortly after
the last squeeze and may decrease before all the channels can be checked. Use the Peak
screen in Display Mode to see the maximum readings for each channel (see pg.39).
NOTE:The peak readings for each channel are saved until a higher peak is recorded, the
peak readings are reset, or the instrument is turned off. If a gas is present but the
level does not exceed the previous peak level, the previous peak will be displayed
on the Peak Screen.
GX-3R Pro Operator’s ManualChapter 3: Operation • 29
This section covers alarm indications in Measuring Mode. It also describes responding to and
resetting an alarm condition.
NOTE:False alarms may be caused by radio frequency (RF) or electromagnetic (EMI)
interference. Keep the GX-3R Pro away from RF and EMI sources such as radio
transmitters or large motors.
Alarm Indications
The GX-3R Pro buzzer sounds an alarm, the LEDs flash, and the vibrator pulses when any
sort of alarm condition or failure occurs. If the GX-3R Pro is operating in Stealth Mode, the
buzzer does not sound and the vibrator’s operation depends on the VIBRATION setting in
Gas Select Mode’s STEALTH menu item. See pg.167 for more information.
NOTE:If an alarm condition occurs while you are in Display Mode, the GX-3R Pro
automatically returns to the Measuring Mode screen.
The table below summarizes the GX-3R Pro’s alarm types and indications.
None of the Man Down alarm indications occur if MAN DOWN is set to OFF (factory
setting) in User Mode. The Panic alarm does not occur if PANIC is set to OFF (factory
setting) in User Mode.
Table 8: Alarm Types and Indications
Alarm TypeVisual IndicationsOther Indications
Warni ng
Concentration of gas rises above the
Warning setting or falls below the
Warning setting for O
Alarm
Concentration of gas rises above the
Alarm setting or falls below the Alarm
setting for O
Alarm H
Concentration of gas rises above the
Alarm H setting.
.
2
.
2
• Affected channel’s gas reading
flashes and the units field alternates
between the units and AL1
• Alarm LEDs flash in circle sequence
once per second
• Backlight turns on
• Affected channel’s gas reading
flashes and the units field alternates
between the units and AL2
• Alarm LEDs flash in circle sequence
twice per second
• Backlight turns on
• Affected channel’s gas reading
flashes and the units field alternates
between the units and AL3
• Alarm LEDs flash in circle sequence
twice per second
• Backlight turns on
• High-low tone sounding
once per second
• Vibrator pulses once per
second
• High-low tone sounding
twice per second
• Vibrator pulses twice per
second
• High-low tone sounding
twice per second
• Vibrator pulses twice per
second
30 • Chapter 3: OperationGX-3R Pro Operator’s Manual
bottom of the LCD and an error code
displays in the middle of the LCD
• Alarm LEDs flash once per second
Man Down Warning 1
The WARNING 1 TIME defined in
User Mode has passed since the
instrument detected movement.
Man Down Warning 2
The WARNING 2 TIME defined in
User Mode has passed since the
instrument detected movement.
Man Down Alarm
The ALARM TIME defined in User
Mode has passed since the instrument
detected movement.
Panic
User double taps the
instrument.
Pre
Alarm
Main
Alarm
• Alarm LEDs flash once per secondSingle pulsing tone once per
• Alarm LEDs flash twice per secondSingle pulsing tone twice per
• MAN DOWN appears at the bottom
of the LCD and the gas readings
disappear
• Alarm LEDs flash in circle sequence
twice per second
• Backlight turns on
• Screen unaffected for 5 seconds
• Alarm LEDs flash twice per second
• PANIC appears at the bottom of the
LCD and the gas readings disappear
• Alarm LEDs flash in circle sequence
twice per second
• Backlight turns on
Double pulsing tone once per
second
second
second
• High-low tone sounding
twice per second
• Vibrator pulses twice per
second
• Single pulsing tone twice
per second for 5 seconds
• High-low tone sounding
twice per second
• Vibrator pulses twice per
second
Responding to Alarms
This section describes response to gas, over range, battery, sensor failure, LIMITED HC GAS
LIST, clock failure, system failure, man down, and panic alarms.
Responding to Gas Alarms
1 .Determine which gas alarm has been activated.
2 .Follow your established procedure for an increasing gas condition or a decreasing
oxygen condition.
3 .Reset the alarm as necessary or allowed.
a. If LATCHING is set to ON (factory setting) in Maintenance Mode, the gas reading
must fall below (or rise above for an oxygen low alarm) an alarm setting before you
can reset the alarm condition using POWER MODE or AIR.
b. If LATCHING is set to OFF in Maintenance Mode, the alarm condition
automatically resets when the gas reading falls below (or rises above for an oxygen
low alarm) an alarm setpoint.
Responding to an H2 RICH Alarm (H2-Compensated CO Sensor Only)
The H2 RICH alarm automatically clears once the hydrogen level decreases below 2000 ppm
(parts per million).
32 • Chapter 3: OperationGX-3R Pro Operator’s Manual
WARNING:An over range condition may indicate an extreme combustible gas, toxic
gas, or oxygen concentration. Confirm the gas concentration with a
different GX-3R Pro or with another gas detecting device.
CAUTION:High off-scale readings may indicate an explosive concentration.
PRUDENCE: Des lectures élevées hors échelle peuvent indiquer une concentration
explosive.
1 .Determine which channel is in alarm.
2 .Follow your established procedure for an extreme gas condition.
3 .If LATCHING is set to ON (factory setting) in Maintenance Mode, reset the alarm
using POWER MODE or AIR once the alarm condition clears.
4 .Calibrate the GX-3R Pro as described on pg.62.
5 .If the over range condition continues or if you are not able to successfully calibrate the
unit, you may need to replace the sensor that has triggered the over range alarm.
6 .If the over range condition continues after you have replaced the sensor, contact RKI
Instruments, Inc. for further instructions.
Responding to Battery Alarms
WARNING:The GX-3R Pro is not operational as a gas monitoring device during a dead
battery alarm. Take the Model GX-3R Pro to a non-hazardous area and
replace or recharge the batteries as described on pg.100 and pg.102.
The GX-3R Pro is fully functional during a low battery warning. Proper instrument operation
is only guaranteed for 10 minutes but the instrument will operate for 1-2 hours after the start
of the alarm.However, only 1-2 hours of operating time remains. The amount of operating
time left depends on LCD backlight use and the alarm frequency. Recharge the Li-ion battery
pack (pg.102) or replace the alkaline batteries (pg.100) as soon as possible.
NOTE:Alarms and the LCD backlight consume battery power and reduce the amount of
operating time remaining.
Responding to Sensor Failure Alarms
1 .Determine which sensor triggered the sensor failure alarm.
2 .Calibrate the failed sensor, as described on pg.62.
3 .If the sensor failure continues or if the sensor could not be calibrated, replace the sensor
as described on pg.107
4 .If the sensor failure condition continues, contact RKI Instruments, Inc. for further
instructions.
GX-3R Pro Operator’s ManualChapter 3: Operation • 33
An HC GAS LIST LIMITED alarm can occur at startup or after a calibration.
1 .Press and release POWER MODE to acknowledge the alarm.
The combustible gas sensor actually contains 2 separate sensors: a standard catalytic sensor
and a backup, poison-resistant sensor that is resistant to sensor poisons like silicone. A
LIMITED HC GAS LIST alarm indicates that the standard sensor has a reduced output,
possibly due to one or more sensor poisons in the environment, and that the poison-resistant
sensor is being used to provide gas readings. The poison-resistant sensor has a limited list of
detectable gases. The table shown on pg.40 shows which gases can and cannot be detected
after receiving a LIMITED HC GAS LIST alarm.
If your application requires detection of a gas still detectable after a LIMITED HC GAS LIST
alarm (like methane or isobutane), there is no need to replace the combustible gas sensor.
However, if your application requires detection of a gas not detectable after a LIMITED HC
GAS LIST alarm (like methanol or ethanol), you must replace the combustible gas sensor as
soon as possible.
Responding to Clock Failure Alarms
A clock failure alarm occurs if the unit’s internal clock malfunctions. A clock failure alarm
might also occur if the battery becomes too drained during storage. See pg.112 for storage
information.
1 .Press and release POWER MODE to continue into Measuring Mode.
CAUTION:If you operate the instrument after a clock failure, data will still be logged but
the date/time will be incorrect. Set the date/time as described on pg.94 as soon
as possible to ensure logged data uses the correct date/time.
2 .Attempt to set the date using the DATE User Mode menu item as described on pg.94.
3 .If the date cannot be set correctly, contact RKI Instruments, Inc. as soon as possible.
34 • Chapter 3: OperationGX-3R Pro Operator’s Manual
1 .If a system failure occurs, an error code displays as shown below:
2 .The error code meanings are shown in the table below:
Table 9: Error Code Explanation
Error CodeExplanation
000ROM failure
010RAM failure
021FRAM failure
031FLASH memory failure
080Acceleration sensor failure
081PCB failure
082Temperature sensor failure
083Bluetooth failure
3 .If the error code is anything but 031, the instrument cannot be used. Contact RKI
Instruments, Inc. as soon as possible.
If the error code is 031, you may press and release POWER MODE to continue into
Measuring Mode if the instrument must be used temporarily.
CAUTION:There will be no datalogging function if you operate the instrument after a 031
system failure. Contact RKI Instruments, Inc. as soon as possible.
Responding to a Man Down Warning 1 and Warning 2
The Man Down Warning 1 and Warning 2 alarms occur after the WA R N I N G 1 TI M E and
WARNING 2 TIME, respectively, has passed since the last movement of the instrument. See
pg.84 for instructions to change these values.
1 .Follow your established procedure for a man down warning.
2 .To silence the alarm and reset the Man Down clock, move the instrument or press and
release POWER MODE.
Responding to a Man Down Alarm
The Man Down Alarm alarms occur after the ALARM TIME has passed since the last
movement of the instrument. See pg.84 for instructions to change this value.
1 .Follow your established procedure for a man down alarm.
2 .To silence the alarm and reset the Man Down clock, press and release POWER MODE
or AIR. Moving the instrument will not reset the alarm or Man Down clock.
GX-3R Pro Operator’s ManualChapter 3: Operation • 35
If the user is in a dangerous situation or feels that others must be alerted to any sort of
problem, forcefully tapping the instrument twice will initiate a panic alarm.
1 .Press and release POWER MODE or AIR to silence and reset the alarm.
Data Logging
The GX-3R Pro logs Measuring Mode gas readings, alarm data, and calibration data to its
internal memory. Logged data can be download it to a computer via the infrared
communications port on the front of the unit.
To utilize the GX-3R Pro’s downloading capability, you will need the GX-3R Data Logger
Management Program and a computer with an infrared port or a USB port that runs one of the
following operating systems: Windows 7, Windows 8, or Windows 10. If your computer has
an infrared port, then no additional accessories are needed to download data from the GX-3R
Pro. If your computer does not have an infrared port but does have a USB port, a USB/IrDA
adapter cable can be used to download data from the GX-3R Pro. The GX-3R Data Logger
Management Program is available at. The USB/IrDA
adapter cable is available from RKI Instruments, Inc.
The data logging capacity depends on how often the GX-3R Pro stores data, how many
channels are active, and how often the GX-3R Pro is turned on and off. The table below
illustrates how much data logging time is available for the various interval times. It assumes
that the unit has four sensors, is only turned on once, and there are no alarm occurrences. The
data logging interval time must be set using the GX-3R Data Logger Management Program.
Table 10: Data Logging Capacity
Interval TimeData Logging Time
10 seconds10 hours
20 seconds20 hours
30 seconds30 hours
1 minute60 hours
3 minutes180 hours
5 minutes (factory setting)300 hours
10 minutes600 hours
For a complete description of the Data Logger Management Program and procedures for
downloading data to a computer, see the GX-3R Data Logger Management Program
Operator’s Manual.
36 • Chapter 3: Operati onGX-3R Pro Operator’s Manual
This section describes Display Mode which is accessible from Measuring Mode. See Table 11
below for a list of Display Mode’s menu items, a short description of each item, and the page
number for further description.
Table 11: Display Mode Menu Items
Display Mode
Menu Item
PEAK (pg.39)Displays each sensor’s Peak reading.
STEL (pg.39)Displays the STEL readings (CO, H
TWA (pg.40)Displays the TWA readings (CO, H
HC GAS LIST
A
(pg.40)
Change the target gas for the catalytic sensor.
•CH4 (methane)
• i-C4H10 (isobutane)
• H2 (hydrogen)
• CH3OH (methanol)
• C2H2 (acetylene)
• C2H4 (ethylene)
• C2H6 (ethane)
• C2H5OH (ethanol)
• C3H6 (propylene)
• C3H6O (acetone)
• C3H8 (propane)
• C4H6 (butyne)
• C5H10 (cyclopentane)
Description
S, and CO2/super toxic only).
2
S, and CO2/super toxic only).
2
• C6H6 (benzene)
• n-C6H14 (hexane)
• C7H8 (toluene)
• n-C7H16 (heptane)
• C8H10 (xylene)
• n-C9H20 (nonane)
• EtAc (ethyl acetate)
• IPA (isopropyl alcohol)
• MEK (methyl ethyl ketone)
• MMA (methyl methacrylate)
• DME (dimethyl ether)
• MIBK (methyl isobutyl ketone)
• THF (tetrahydrofuran)
USER ID
C
(pg.42)
STATION ID
C
(pg.43)
CAL DATA
D
(pg.43)
BUMP DATA
E
(pg.44)
DATE (pg.45)Displays the current date, time, and temperature.
ALARM
POINTS
(pg.46)
INVERT
SELECT
B
(pg.47)
View and/or change the User ID.
View and/or change the Station ID.
Displays the last calibration date for each sensor.
Displays the last bump test date for each sensor.
View alarm points
ON: The LCD stays upside down relative to the instrument.
AUTO: The LCD automatically flips as the instrument is rotated to remain readable
whether the instrument is right side up or upside down.
OFF (factory setting): The LCD stays right side up relative to the instrument.
GX-3R Pro Operator’s ManualChapter 4: Display Mode • 37
The peak screen displays the highest (lowest for oxygen) concentrations detected since the
GX-3R Pro was turned on. Peak readings are stored in the GX-3R Pro’s memory until a higher
level is detected (lower for oxygen), the peak reading is cleared, or the GX-3R Pro is turned
off.
The lunch break feature enables the GX-3R Pro to save peak readings when it is turned off so
it can continue with the same peaks when it is turned on again. See pg.88 for instructions to
turn the lunch break feature on (default is off).
To clear the peak readings, do the following:
1 .While in Display Mode, press and release POWER MODE until PEAK appears.
2 .Press and hold AIR until the screen prompts you to release it.
3 .The peak readings are reset and the unit returns to the Peak Screen.
If you do not want to clear the peak readings, release AIR before the above screen
sequence occurs. The unit returns to the Peak Screen.
STEL Screen (STEL)
The STEL Screen displays the short term exposure limit (STEL) readings for H2S, CO, CO2,
and super toxic only. The STEL reading is the average reading over the last 15 minutes.
GX-3R Pro Operator’s ManualChapter 4: Display Mode • 39
The TWA Screen displays the time weighted average (TWA) readings for H2S, CO, CO2, and
super toxic only.
The TWA reading is the average reading over the last 8 hours. If 8 hours have not elapsed
since the last time the TWA reading was cleared, the average is still calculated over 8 hours.
The missing readings are assigned a 0 value. If LUNCH BREAK is set to OFF (factory
setting), the TWA is cleared when the GX-3R Pro is turned off.
If LUNCH BREAK is set to ON, the GX-3R Pro will remember TWA readings when it is
turned off so it can continue them when it is turned on again. See pg.88 for instructions to turn
the lunch break feature on (default is off).
Combustible Sensor Target Gas Conversion (HC GAS LIST)
This screen only appears if D MODE SETTING in User Mode is set to ON (factory setting)
and if the instrument’s calibrated target gas is CH4 or iC4H10 (select target gas in Gas Select
Mode’s GAS COMBO item, calibrate with target gas in User Mode’s GAS CAL item).
The HC GAS LIST screen allows you to select a converted target gas based on a CH4 or
iC4H10 calibration. It does not change the calibrated target gas. You must go to Gas Select
Mode’s GAS COMB item to change the calibrated target gas.
Selecting a converted target gas in HC GAS LIST (based on a CH4 or iC4H10 calibration)
does not provide the same reading accuracy as selecting a calibrated target gas in Gas Select
Mode’s GAS COMBO item and calibrating with that target gas in User Mode.
Selecting a converted target gas in HC GAS LIST does not mean that the combustible gas
sensor will respond only to that gas. The combustible gas sensor responds to a number of
gases regardless of the target gas selection.
However, if H2 is selected as the target gas in HC GAS LIST, the sensor will not respond to
the gases listed with an “x” in the “Available Target Gas Conversions During LIMITED HC
GAS LIST Status” column of the table below.
If you select a new converted target gas, the change is saved if you turn the instrument off and
on.
40 • Chapter 4: Display ModeGX-3R Pro Operator’s Manual
2 .Press and release AIR to enter the screen. A cursor appears to the left of the current gas
7:49
CH4
i-C4H10
H2
HC GAS LIST
7:49
U_ID_002
CHANGE : AIR
USER ID
7:49
U_ID_002
NO : MODE
USER ID
7:49
U_ID_002
USER ID
selection.
3 .Use AIR to scroll through the list of gases.
4 .With the cursor next to the desired gas, press and release POWER MODE. The
instrument saves the changes and returns to the HC GAS LIST screen.
5 .The gas formula displays at the bottom of the Measuring Mode screen. The gas selection
remains in effect if you turn the instrument off and on again.
User ID Screen (USER ID)
This screen only appears if D MODE SETTING in User Mode is set to ON (factory setting)
and
if ID DISPLAY in Maintenance Mode is set to ON (factory setting is OFF).
Use this screen to select a user ID from the 128 user IDs stored in the GX-3R Pro’s memory.
Before a user ID is selected on a brand new instrument, the user ID is “----------”. The factoryinstalled user IDs have a “U_ID_XXX” format.
The user ID provides a way to identify the GX-3R Pro user during a data logging session.
User IDs can only be selected in this menu item. You must use the GX-3R Datalogging
Program to edit the 128 user IDs.
1 .After entering Display Mode, press and release POWER MODE until USER ID appears.
2 .To change the User ID, press and release AIR. The current User ID flashes.
3 .Use AIR to scroll to the desired User ID.
4 .Press and release POWER MODE to save the User ID and return to the USER ID screen
in Display Mode.
42 • Chapter 4: Display ModeGX-3R Pro Operator’s Manual
This screen only appears if D MODE SETTING in User Mode is set to ON (factory setting)
and if ID DISPLAY in Maintenance Mode is set to ON (factory setting is OFF).
Use this screen to select a station ID from the 128 station IDs stored in the GX-3R Pro’s
memory. Before a station ID is selected on a brand new instrument, the station ID is
“----------”. The factory-installed station IDs have a “S_ID_XXX” format.
The station ID provides a way to identify the GX-3R Pro location during a data logging
session.
User IDs can only be selected in this menu item. You must use the GX-3R Datalogging
Program to edit the 128 station IDs.
1 .After entering Display Mode, press and release POWER MODE until STATION ID
appears.
2 .To change the Station ID, press and release AIR. The current Station ID flashes.
3 .Use AIR to scroll to the desired Station ID.
4 .Press and release POWER MODE to save the Station ID and return to the STATION ID
screen in Display Mode.
Last Successful Calibration Date (CAL DATA)
The CAL DATA screen shows the date of each installed sensors’ last successful calibration.
This screen only appears if CAL REMINDER is set to ON in User Mode.
1 .While in Display Mode, press and release POWER MODE until CAL DATA appears.
GX-3R Pro Operator’s ManualChapter 4: Display Mode • 43
2 .Press AIR to enter the CAL DATA screen and to scroll through the installed sensors.
AIR
AIR
AIR
7:49
MM/DD/YYYY
10/16/2018
CH4
CAL DATA
7:49
MM/DD/YYYY
10/16/2018
O2
CAL DATA
7:49
MM/DD/YYYY
10/16/2018
H2S
CAL DATA
7:49
MM/DD/YYYY
10/16/2018
CO
CAL DATA
7:49
MM/DD/YYYY
10/16/2018
CO2
CAL DATA
AIR
AIR
7:49
YES : AIR
NO : MODE
BUMP DATA
3 .When you are done viewing the last calibration date for the sensors, press and release
POWER MODE to return to the CAL DATA screen in Display Mode.
Last Successful Bump Test Date (BUMP DATA)
The BUMP DATA screen shows the date of each installed sensors’ last successful bump test.
This screen only appears if BUMP REMINDER is set to ON in User Mode.
1 .While in Display Mode, press and release POWER MODE until BUMP DATA appears.
44 • Chapter 4: Display ModeGX-3R Pro Operator’s Manual
The Alarm Points Screen shows the gas alarm settings for all active channels.
1 .While in Display Mode, press and release POWER MODE until ALARM POINTS
appears.
2 .Press and release AIR to enter the Alarm Points screen. The Full Scale Settings screen
appears and shows full scale settings for each channel.
3 .Use AIR to scroll through the Warning, Alarm, Alarm H, STEL, and TWA settings.
4 .While viewing the alarm settings for a particular alarm point, press and release AIR and
POWER MODE at the same time to simulate the alarm conditions. The buzzer will
sound, the LEDs will flash, and the instrument will vibrate just as it would if the
displayed condition was actually happening.
5 .Press and release POWER MODE to return to the ALARM POINTS item in Display
Mode.
46 • Chapter 4: Display ModeGX-3R Pro Operator’s Manual
The INVERT SELECT screen allows you to turn the screen inversion function on or off.
This screen only appears if D MODE SETTING in User Mode is set to ON (factory setting).
ON: The LCD stays upside down relative to instrument.
AUTO: The LCD automatically flips to remain readable whether the instrument is right side
up or upside down.
OFF (factory setting): The LCD stays right side up relative to the instrument.
1 .While in Display Mode, press and release POWER MODE until INVERT SELECT
appears. The current setting displays on the top line.
2 .Press and release AIR. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the INVERT
SELECT screen.
LCD Color Scheme (LCD BACKGROUND)
The LCD BACKGROUND screen allows you to change the appearance of the LCD. This
screen only appears if D MODE SETTING in User Mode is set to ON (factory setting).
ON: LCD has black background with white characters.
OFF (factory setting): LCD has white background with black characters.
1 .While in Display Mode, press and release POWER MODE until LCD BACKGROUND
appears. The current setting displays on the top line.
2 .Press and release AIR. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the LCD
BACKGROUND screen.
GX-3R Pro Operator’s ManualChapter 4: Display Mode • 47
The BLUETOOTH screen allows you to turn the GX-3R Pro’s Bluetooth functionality on
and off. This screen only appears if D MODE SETTING in User Mode is set to ON (factory
setting).
ON: Turns Bluetooth functionality on, allowing for connection to the RK Link app on your
phone.
If BLE Auto Shut Off When Idle, accessible in the Datalogging or SDM-3R Program, is
selected (factory setting) and if the GX-3R Pro does not pair to a phone in the first 5 minutes
after startup, the GX-3R Pro’s Bluetooth gets shut off to conserve battery life.
If BLE Auto Shut Off When Idle, accessible in the Datalogging or SDM-3R Program, is
deselected and if the GX-3R Pro does not pair to a phone, the GX-3R Pro’s Bluetooth stays on
indefinitely.
OFF (factory setting): Turns Bluetooth functionality off.
1 .While in Display Mode, press and release POWER MODE until BLUETOOTH
appears. The current setting displays on the top line.
2 .Press and release AIR. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BLUETOOTH
screen.
Adjusting the Buzzer Volume (BUZZER VOLUME)
The BUZZER VOLUME screen allows you to adjust the volume of the instrument’s buzzer.
This screen only appears if D MODE SETTING in User Mode is set to ON (factory setting).
HIGH (factory setting): Buzzer volume is high.
LOW: Buzzer volume is low.
1 .While in Display Mode, press and release POWER MODE until BUZZER VOLUME
appears. The current setting displays on the top line.
2 .Press and release AIR. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUZZER
VOLUME screen.
48 • Chapter 4: Display ModeGX-3R Pro Operator’s Manual
This section describes the GX-3R Pro in User Mode. See Table 12 below for a list of the items
found in User Mode, the page that the menu item’s instructions can be found on, and a short
description of the menu item.
Table 12: User Mode Menu Items
User Mode
Menu Item
BUMP TEST
(pg.56)
GAS CAL (pg.62)Perform a fresh air adjustment, perform a span adjustment, change the calibration gas concen-
Perform a bump test.
BUMP TEST
CYL X
START
MEASURE
ESCAPEReturn to BUMP TEST menu item.
tration, set the cylinder group.
AIR CAL (pg.62)Perform a fresh air adjustment.
CO2 ZERO CAL
(pg.63)***
AUTO CAL
(pg.65)
Perform a bump test on the gases selected for Cylinder X
(A-E cylinders available).
Begin the warmup sequence and enter Measuring Mode.
Perform a zero adjustment on the CO
AUTO CAL
CYL X
START
MEASURE
SETTING
CAL-P
Description
channel using 100% nitrogen.
2
Perform an automatic span adjustment on the gases
selected for Cylinder X (A-E cylinders available).
Begin the warmup sequence and enter Measuring
Mode.
Set the calibration gas concentration for each gas.
CAL SETTING
(pg.75)
CYL
SETTING
ESCAPEReturn to the AUTO CAL menu item.
ESCAPEReturn to the GAS CAL menu item.
Change calibration parameters.
CAL
REMINDER
(pg.76)
CAL
INTERVAL
(pg.76)
ON
(factory setting): The instrument notifies the user upon startup when a
calibration is due. Notification type depends on CAL EXPD setting
below.
OFF
: No notification upon startup when a calibration is due.
How often the instrument needs to be calibrated.
Options: 1 - 1000 days (factory setting is 90 days)
Assign a cylinder (A-E) to each gas. Multiple gases can
be assigned to the same cylinder.
50 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
ESCAPEReturn to the BUMP SETTING menu item in User Mode.
Turn the man down and panic alarms on and off. Set the intervals for man down alarms.
MAN DOWN
(pg.83)
PANIC (pg.83)ON
MAN DOWN
TIME (pg.84)
ALL GAS (factory setting): Bump test dates for all gases are used to
determine if bump test is due.
4 GAS
: Bump test dates for only the standard 4 gases (combustible gas/
O
S/CO) are used to determine if bump test is due.
2/H2
ON
: Man down alarm is triggered if the instrument does not detect motion
during time period defined in WARNING 1 TIME, WARNING 2 TIME,
and ALARM TIME below.
OFF
(factory setting): No man down alarm triggered.
: Panic alarm can be triggered.
OFF
(factory setting): Panic alarm cannot be triggered.
ALARM TIME WARNING 2 TIME WARNING 1 TIME
WARNING 1
TIME
WARNING 2
TIME
The amount of time that passes between a man down
detection and the first warning alarm. Factory setting is
60 seconds.
The amount of time that passes between a man down
detection and the second warning alarm. Factory set-
ting is 75 seconds.
ALARM
SETTING (pg.85)
LUNCH BREAK
(pg.88)
ALARM TIMEThe amount of time that passes between a man down
detection and a man down alarm. Factory setting is 90
seconds.
ESCAPEReturn to the MAN DOWN menu item.
Set alarm points for all channels (WARNING, ALARM, ALARM H, STEL, TWA) or reset all
alarms to their default settings.
ON
: Lunch break feature is on. At startup, instrument asks if you want to resume TWA and
PEAK readings.
OFF
(factory setting): Lunch break feature is off. Instrument resets TWA and PEAK readings
every time it’s turned on.
52 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
: LEDs flash and instrument vibrates based on interval defined in
BEEP INTERVAL to confirm instrument is still operating.
BUZZER
: Buzzer sounds and instrument vibrates based on interval
defined in BEEP INTERVAL to confirm instrument is still operating.
LED+BUZZER
based on interval defined in BEEP INTERVAL to confirm instrument is
still operating.
BUMP/CAL
VA L if bump test or calibration is due.
ALARM ALERT
INTERVAL if instrument goes into a gas alarm.
BUMP/CAL/ALARM
INTERVAL if a) bump test is due, b) calibration is due, or c) instrument
goes into a gas alarm.
OFF
(factory setting): No alerts to confirm instrument is still operating or
that a bump test or calibration are due.
BEEP
INTERVAL
(pg.90)
Confirmation alert interval. Confirmation type defined in BEEP SELECT.
Options: 0.5 minute and 1 to 99 minutes in 1 minute increments. Factory
setting is 5 minutes.
Description
: LEDs flash, buzzer sounds, and instrument vibrates
: LEDs flash based on interval defined in BEEP INTER-
: LEDs flash based on interval defined in BEEP
: LEDs flash based on interval defined in BEEP
ESCAPEReturn to the CONFIRMATION menu item in User Mode.
AUTO
BACKLIGHT
(pg.91)
BACKLIGHT
TIME (pg.91)
ON
ment.
OFF
How long the back light stays on after the last button press.
Options: 0 - 255 seconds or OFF. The factory setting is 30 seconds.
KEY TONE (pg.92)ON
OFF
D MODE
SETTING (pg.92)
OFF
TOOTH, BUZZER VOLUME, and LANGUAGE items do not appear in Display Mode.
ON
BUZZER VOLUME, and LANGUAGE items appear in Display Mode. USER ID and STA-
TION ID screens appear if ID DISPLAY in Maintenance Mode is also set to ON.
ZERO SUPPRESS
(pg.93)*
ON
Combustible Gas: 2% LEL
O
2
H
2
CO: 2 ppm
CO
HCN: 0.5 ppm
NH
NO
PH
SO
(factory setting): The instrument’s backlight automatically turns on in a low light environ-
: The instrument’s backlight does not automatically turn on in a low light environment.
(factory setting): Buzzer sounds when a button is pressed.
: Buzzer does not sound when a button is pressed.
: LIST, USER ID, STATION ID, INVERT SELECT, LCD BACKGROUND, BLUE-
Not intended for field adjustment. The default setting is ON for every channel except oxygen.
Oxygen channel does not support zero follower functionality.
Select the units for the IR CO
Options: vol% or ppm
ON
: CO2 channel is set to 400 ppm (0.04% volume) during a demand zero, auto zero, or AIR
CAL.
OFF
(factory setting): CO2 channel is not adjusted during a demand zero, auto zero, or AIR
CAL.
MM/DD/YYYY
YYYY/MM/DD
DD/MM/YYYY
Set the instrument language.
Options: English (factory setting), Japanese, Italian, Spanish, German, French, Portuguese,
Russian, Korean, Chinese (TC)
ON
: User Mode access is password-protected. Factory-set password is 0405.
OFF
(factory setting): User Mode access is not password-protected.
ROM/SUM (pg.96)View the firmware information for the GX-3R Pro’s sensor board and main board.
RADIO
STANDARD
(pg.97)
START
MEASURE (pg.98)
* Only appears if DISP ZERO SUP is set to ON in Maintenance Mode.
** Only appears if DISP ZERO FLWR is set to ON in Maintenance Mode.
*** Only appears in units with a CO
Approval numbers for radio agencies.
Press and release POWER MODE to begin the warmup sequence and enter Measuring Mode.
sensor installed.
2
Entering User Mode
WARNING:The GX-3R Pro is not in operation as a gas detector while in User Mode.
1 .Take the GX-3R Pro to a non-hazardous location and turn it off if it is on.
2 .Press and hold AIR, then press and hold POWER MODE. Release the buttons when you
hear a beep.
54 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
3 .The screen that appears depends on the setting of User Mode’s USER PASSWORD
USER PASSWORD
set to
OFF USER PASSWORD
set to
ON
MAINTE 7:49
BUMP TEST
GAS CAL
CAL SETTING
USER MODE
MAINTE 7:49
0000
PASSWORD
MAINTE 7:49
BUMP TEST
GAS CAL
CAL SETTING
USER MODE
MAINTE
item.
If USER PASSWORD is set to OFF (factory setting), continue with Step 6.
If USER PASSWORD is set to ON, continue with Step 4.
4 .If USER PASSWORD in User Mode is set to ON, a password screen appears and the
first digit flashes.
5 .Use AIR to select each password number then press POWER MODE to save it and move
on to the next number. To go back a number, press and hold AIR and POWER MODE
for a few seconds. To reverse the direction of change (ie. from increasing to decreasing
or vice versa):
a. Press and hold AIR.
b. Immediately press POWER MODE and then release both buttons.
6 .The User Mode menu displays.
7 .at the top of the screen indicates that the GX-3R is in User Mode.
8 .Use AIR to move through the User Mode menu items.
Tips for Using User Mode
•To scroll from one menu item to the next, press and release AIR. To reverse the scrolling
direction:
a. Press and hold AIR.
b. Immediately press POWER/MODE and then release both buttons.
c. The scrolling direction returns to the original direction when you exit and reenter a
menu.
•To skip an item when a question is asked, press and release AIR.
•To enter an item and to save any changes, press and release POWER MODE.
•To change a flashing parameter, press and release AIR. To reverse the direction of change
(ie. from increasing to decreasing or vice versa):
a. Press and hold AIR.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 55
b. Immediately press POWER MODE and then release both buttons.
•To exit an entered menu item without saving a change, press and hold AIR and POWER
MODE for a few seconds.
Performing a Bump Test (BUMP TEST)
Bump test the instrument before each day’s use with a known concentration of each target gas.
The instrument does not need to be calibrated unless it does not pass the bump test.
To bump test the GX-3R Pro, you will need:
•Known calibrating samples of the gases being detected.
Table 13: Calibration Gas Concentration Limits
Channel
Combustible Gas5% LEL75% LEL
Oxygen0.0%18.0%
Hydrogen Sulfide1.0 ppm200.0 ppm
Carbon Monoxide15 ppm2,000 ppm
Ammonia8 ppm400 ppm
Carbon Dioxide (0 - 10,000 ppm)3,000 ppm9,000 ppm
Carbon Dioxide (0 - 10.00% vol)1.00% vol4.00% vol
Hydrogen Cyanide0.9 ppm30.0 ppm
Nitrogen Dioxide0.50 ppm20.00 ppm
Phosphine0.05 ppm20.00 ppm
Sulfur Dioxide0.50 ppm100.00 ppm
•A 0.25 LPM fixed flow regulator
•Non-absorbent tubing
Min. Cal. Gas
Concentration
Max. Cal. Gas
Concentration
•Calibration cup
1 .Confirm that the GX-3R Pro’s calibration gas values match the concentrations listed on
the calibration gas cylinder(s) as described on pg.71.
2 .Confirm that your cylinder selections are appropriate as described on pg.73.
56 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
3 .Install the calibration cup onto the GX-3R Pro. Use the label and imprinting to make sure
CO/H2S LEL O2 TOXIC
GX-3R Pro
AIR
POWER
MODE
Inlet
FRONT
Figure 7: Calibration Cup Installation
MAINTE 7:49
BUMP TEST
GAS CAL
CAL SETTING
USER MODE
MAINTE 7:49
12.0
O2 %
50 50 25.0
CH4 %LEL CO ppm H2S ppm
BUMP TEST CYLINDER A
that the calibration cup gets installed in the correct orientation relative to the GX-3R Pro.
Be sure the calibration cup is pushed on all the way.
4 .Use the tubing to connect the regulator to the inlet of the calibration cup.
5 .While in User Mode, use AIR to place the cursor next to BUMP TEST.
6 .Press and release POWER MODE. The display shows the gases assigned to Cylinder A
and their assigned calibration values (see pg.71 if the calibration values do not match the
calibration gas cylinder’s concentrations).
7 .If necessary, use AIR to scroll to the Bump screen for the gas(es) you want to bump test.
As shipped from the factory, the standard 4 gases (combustible gas, O
, CO, and H2S)
2
are assigned to Cylinder A. If a H2-compensated CO sensor is installed, H2 is assigned to
Cylinder D but there is no reason to bump test the H2 response. Toxic sensors are
assigned to Cylinder D or Cylinder E.
8 .Make sure the GX-3R Pro has been turned on for at least 45 seconds before continuing.
9 .For toxic gas cylinders (like cylinders containing H
S), it is important to vent the
2
regulator while installing it onto the cylinder. Venting the regulator during installation
helps prevent air from getting into the cylinder and degrading the gas. Open the regulator
by turning the knob counterclockwise and install it onto the cylinder.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 57
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 61
5. Unscrew the regulator.
6. Remove the calibration cup.
7. Press and release POWER MODE to
enter Measuring Mode.
www.GlobalTestSupply.com
4. Close the regulator.
5. Unscrew the regulator.
6. Remove the calibration cup.
7. Press and release POWER MODE to
return to the START item in the BUMP
menu.
8. Press and release POWER MODE to
enter Measuring Mode.
Performing a Calibration (GAS CAL)
MAINTE 7:49
BUMP TEST
GAS CAL
CAL SETTING
USER MODE
MAINTE 7:49
AIR CAL
CO2 ZERO CAL
AUTO CAL
GAS CAL
MAINTE 7:49
20.9
O2 %
0 0 0.0
CH4 %LEL CO ppm H2S ppm
AIR CAL
Calibration Notes
•To fully calibrate the standard 4 (combustible gas, O2, CO, H2S) and super toxic sensors,
you must do a fresh air adjustment (AIR CAL) and a span adjustment (AUTO CAL).
•To fully calibrate the IR CO2 sensor, you must do either a) a fresh air adjustment (AIR CAL) and
and a span adjustment (AUTO CAL).
•Bump test the instrument before each day’s use with a known concentration of each target
gas. A bump test can be done in User Mode’s BUMP TEST item or by applying gas in
Measuring Mode. The instrument does not need to be calibrated unless it does not pass the
User Mode bump test or does not respond appropriately, as defined by the user, in
Measuring Mode.
•The hydrogen response for the H
sensor is replaced.
Performing a Fresh Air Adjustment (AIR CAL)
1 .Find a fresh air environment, an environment of normal oxygen content (20.9%) that is
free of toxic and combustible gases.
2 .While in User Mode, use AIR to place the cursor next to GAS CAL.
a span adjustment (AUTO CAL) or b) a zero adjustment (CO2 ZERO CAL)
-compensated CO sensor only needs to be set when the
2
3 .Press and release POWER MODE. The Gas Cal menu appears.
4 .Use AIR to place the cursor next to AIR CAL.
5 .Press and release POWER MODE. The example below shows the standard 4 sensors
(combustible gas, O
6 .Make sure the GX-3R Pro has been turned on for at least 45 seconds before continuing.
, CO, H2S).
2
62 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
7 .Press and hold AIR until the screen prompts you to release it.
MAINTE 7:49
HOLD AIR KEY
AIR CAL
MAINTE 7:49
ADJUSTING ZERO
RELEASE
CO/H2S LEL O2TOXIC
GX-3R Pro
AIR
POWER
MODE
Inlet
FRONT
Figure 9: Calibration Cup Installation
8 .If the fresh air adjustment passes, the instrument returns to the Gas Cal menu.
9 .If the fresh air adjustment fails, “FAIL AIR” displays. Press and release POWER MODE
to acknowledge the failure. See “Troubleshooting” on page 99.
Performing a Zero Adjustment on the CO2 Sensor
(CO2 ZERO CAL)
Performing a zero adjustment on the CO2 sensor sets the sensor’s zero to a known
concentration of CO2 (0 ppm or 0%).
Preparing for a CO2 ZERO CAL
To set the zero reading on the CO
•100% nitrogen (N
) cylinder
2
•0.25 LPM fixed flow regulator
sensor, you will need:
2
•Non-absorbent tubing
•Calibration cup
1 .Confirm that the regulator knob is turned all the way clockwise. Screw the 0.25 LPM
fixed flow regulator onto the calibration cylinder.
2 .Install the calibration cup onto the GX-3R Pro. Use the label and imprinting to make sure
that the calibration cup gets installed in the correct orientation relative to the GX-3R Pro.
Be sure the calibration cup is pushed on all the way.
3 .Use the tubing to connect the regulator to the inlet of the calibration cup.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 63
1 .While in User Mode, use AIR to place the cursor next to GAS CAL.
2 .Press and release POWER MODE. The Gas Cal menu appears.
3 .Use AIR to place the cursor next to CO2 ZERO CAL.
4 .Make sure the GX-3R Pro has been turned on for at least 45 seconds before continuing.
5 .Press and release POWER MODE.
6 .The CO2 gas reading flashes and the bottom of the screen indicates “CO2 ZERO CAL”
and “APPLY GAS”.
NOTE:To back out of the gas application screen without performing the bump test, press
and release AIR and POWER MODE together.
7 .Turn the regulator knob counterclockwise to open the regulator.
8 .Allow the gas to flow for 1 minute.
9 .Press and release POWER MODE.
10 . Turn the regulator knob clockwise to close the regulator.
11 . If the zero adjustment passed
Gas Cal menu.
64 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
the screen says “PASS” and the instrument returns to the
12 . If the zero adjustment failed:
MAINTE 7:49
FAIL
CO2 vol%
CO2 ZERO CAL
a. “FAIL” replaces the gas reading.
b. The LEDs flash and the buzzer sounds a double pulsing tone.
c. Press and release POWER MODE to clear the failure. The instrument returns to the
GAS CAL menu.
d. See “Troubleshooting” on page 99.
13 . Unscrew the regulator from the calibration cylinder.
14 . Remove the calibration cup from the GX-3R Pro.
15 . Store the calibration kit in a safe and convenient place.
16 . Use AIR to place the cursor next to ESCAPE.
17 . Press and release POWER MODE. The instrument returns to User Mode.
Performing a Span Adjustment in AUTO CAL
Preparing for a Span Adjustment
To perform a span adjustment on the GX-3R Pro, you will need:
•Known concentrations of the gases being detected.
Table 14: Calibration Concentration Limits
Channel
Combustible Gas5% LEL75% LEL
Oxygen0.0%18.0%
Hydrogen Sulfide1.0 ppm200.0 ppm
Carbon Monoxide15 ppm2,000 ppm
Hydrogen (for H
CO sensor); only needs to be done
when sensor is replaced
Ammonia8 ppm400 ppm
Carbon Dioxide (0 - 10,000 ppm)3,000 ppm9,000 ppm
Carbon Dioxide (0 - 10.00% vol)1.00% vol4.00% vol
Hydrogen Cyanide0.9 ppm30.0 ppm
Nitrogen Dioxide0.50 ppm20.00 ppm
Phosphine0.05 ppm20.00 ppm
-compensated
2
Min. Cal.
Concentration
25 ppm2,000 ppm
Max. Cal.
Concentration
Sulfur Dioxide0.50 ppm100.00 ppm
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 65
1 .Confirm that the GX-3R Pro’s calibration gas values match the concentrations listed on
the calibration gas cylinder(s) as described on pg.71.
2 .Confirm that your cylinder selections are appropriate as described on pg.73.
3 .Install the calibration cup onto the GX-3R Pro. Use the label and imprinting to make sure
that the calibration cup gets installed in the correct orientation relative to the GX-3R Pro.
Be sure the calibration cup is pushed on all the way.
4 .Use the tubing to connect the regulator to the inlet of the calibration cup.
Performing a Span Adjustment
1 .While in User Mode, use AIR to place the cursor next to GAS CAL.
2 .Press and release POWER MODE. The Gas Cal menu appears.
3 .Use AIR to place the cursor next to AUTO CAL.
66 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
4 .Press and release POWER MODE. The display shows the gases assigned to Cylinder A
MAINTE 7:49
12.0
O2 %
50 50 25.0
CH4 %LEL CO ppm H2S ppm
AUTO CAL CYLINDER A
MAINTE 30
20.9
O2 %
0 0 0.0
CH4 %LEL CO ppm H2S ppm
AUTO CAL APPLY GAS
and the assigned calibration values (see pg.71 if the calibration values do not match the
calibration gas cylinder’s concentrations).
5 .If necessary, use AIR to scroll to the Auto Cal screen for the gas(es) you want to
calibrate. As shipped from the factory, the standard 4 gases (combustible gas, O2, CO,
and H2S) are assigned to Cylinder A. If a H2-compensated CO sensor is installed, H2 is
assigned to Cylinder D but there is no reason to bump test the H
response. Toxic sensors
2
are assigned to Cylinder D or Cylinder E.
6 .Make sure the GX-3R Pro has been turned on for at least 45 seconds before continuing.
7 .Press and release POWER MODE.
8 .The gas readings flash and the bottom of the screen indicates “AUTO CAL” and
“APPLY GAS”.
NOTE:To back out of the gas application screen without performing the bump test, press
and release AIR and POWER MODE together.
9 .For toxic gas cylinders (like cylinders containing H2S), it is important to vent the
regulator while installing it onto the cylinder. Venting the regulator during installation
helps prevent air from getting into the cylinder and degrading the gas. Open the regulator
by turning the knob counterclockwise and install it onto the cylinder.
10 . Allow the gas to flow for 1 minute for all gases except NH3. Allow NH3 gas to flow for
2 minutes.
11 . Press and release POWER MODE.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 67
1. The instrument indicates that all channels passed the
calibration.
2. The instrument shows the current gas readings.
3. If DISP MAX SPAN is set to ON (default is OFF, see
pg.166), the response reading’s maximum adjustment
displays. A maximum span of 100% LEL on the combustible
channel indicates that the reading could have been adjusted
up to 100% LEL. If the maximum span value is close to the
calibration gas value, the sensor should be replaced soon.
The maximum adjustment is either twice the calibration value
or full scale, whichever is lower. The maximum adjustment
for the oxygen channel is 25.0% volume.
• Calibration passed
• One cylinder assigned
• Auto Start After Successful Cal set to ON (factory setting)
1. The instrument indicates that all channels passed the
calibration.
2. The instrument shows the current gas readings.
3. If DISP MAX SPAN is set to ON (default is OFF, see
pg.166), the response reading’s maximum adjustment
displays. A maximum span of 100% LEL on the combustible
channel indicates that the reading could have been adjusted
up to 100% LEL. If the maximum span value is close to the
calibration gas value, the sensor should be replaced soon.
The maximum adjustment is either twice the calibration value
or full scale, whichever is lower. The maximum adjustment
for the oxygen channel is 25.0% volume.
4. If the combustible gas sensor is nearing the end of its useful
life, the reading conversions that can be made in Display
Mode’s HC GAS LIST item become limited. Press and
release POWER MODE. See pg.40 for the limited conversion
list. Replace the combustible sensor as soon as possible.
5. Close the regulator.
6. The instrument continues to the AUTO CAL CYL X screen.
7. Unscrew the regulator from the first cylinder and screw it into
the next cylinder.
8. Press and release POWER MODE to start the next cylinder’s
calibration.
4. If the combustible gas sensor is nearing the end of its useful
life, the reading conversions that can be made in Display
Mode’s HC GAS LIST item become limited. Press and
release POWER MODE. See pg.40 for the limited conversion
list. Replace the combustible sensor as soon as possible.
5. Close the regulator.
6. Unscrew the regulator.
7. Remove the calibration cup.
8. The instrument automatically begins its warmup sequence
and enters Measuring Mode.
9. Repeat Step 9 through Step 12.
10. After the last cylinder is calibrated, the instrument continues
to the START MEASURE item in the AUTO CAL menu.
11. Remove the calibration cup.
12. Press and release POWER MODE to enter Measuring Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 69
www.GlobalTestSupply.com
Option C from Flow ChartOption D from Flow Chart
7:49
PASS
AUTO CAL
MAINTE 7:49
11.9
O2 %
47 47 23.3
CH4 %LEL CO ppm H2S ppm
AUTO CAL
MAINTE 7:49
25.0
O2 %
100 70 48.5
CH4 %LEL CO ppm H2S ppm
MAX SPAN
7:49
LIMITED
HC GAS LIST
MAINTE 7:49
11.9
O2 %
FAIL 47 23.3
CH4 %LEL CO ppm H2S ppm
AUTO CAL
• Calibration passed
• One cylinder assigned
• Auto Start After Successful Cal set to OFF (factory setting is
ON)
1. The instrument indicates that all channels passed the
calibration.
2. The instrument shows the current gas readings.
3. If DISP MAX SPAN is set to ON (default is OFF, see
pg.166), the response reading’s maximum adjustment
displays. A maximum span of 100% LEL on the combustible
channel indicates that the reading could have been adjusted
up to 100% LEL. If the maximum span value is close to the
calibration gas value, the sensor should be replaced soon.
• Calibration failed
1. The instrument indicates which channels failed the
calibration.
2. Close the regulator.
3. Unscrew the regulator.
4. Remove the calibration cup.
5. Press and release POWER MODE to return to the AUTO
CAL CYL X screen in the AUTO CAL menu.
6. See “Troubleshooting” on page 99.
The maximum adjustment is either twice the calibration value
or full scale, whichever is lower. The maximum adjustment
for the oxygen channel is 25.0% volume.
4. If the combustible gas sensor is nearing the end of its useful
life, the reading conversions that can be made in Display
Mode’s HC GAS LIST item become limited. Press and
release POWER MODE. See pg.40 for the limited conversion
list. Replace the combustible sensor as soon as possible.
5. Close the regulator.
6. Unscrew the regulator.
7. Remove the calibration cup.
8. The instrument continues to the START MEASURE item in
the AUTO CAL menu.
9. Press and release POWER MODE to enter Measuring Mode.
7 .Use AIR to scroll to the channel whose calibration gas value you want to change.
AIR
AIR
AIR
AIR
MAINTE 7:49
- - - -
CH4 %LEL
SETTING CAL--P
MAINTE 7:49
- - - -
O2 %
SETTING CAL--P
AIR
MAINTE 7:49
- - - -
H2S ppm
SETTING CAL--P
MAINTE 7:49
- - - -
CO ppm
SETTING CAL--P
MAINTE 7:49
- - - -
CO2 vol%
SETTING CAL--P
MAINTE 7:49
ESCAPE
8 .Press and release POWER MODE. The calibration gas value begins to flash. In the
example below, the combustible gas channel is selected.
9 .Use AIR to adjust the calibration gas value. The calibration gas value in the instrument
must match the value listed on the calibration gas cylinder you are using for that channel.
Limits on the calibration gas value are shown in the table below.
Combustible Gas5% LEL75% LEL
Oxygen0.0%18.0%
Hydrogen Sulfide1.0 ppm200.0 ppm
Carbon Monoxide15 ppm2,000 ppm
Hydrogen (for H
CO sensor); only needs to be done
when sensor is replaced
Ammonia8 ppm400 ppm
Table 15: Calibration Concentration Limits
Channel
Min. Cal.
Concentration
Max. Cal.
Concentration
-compensated
2
25 ppm2,000 ppm
72 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
10 . Press and release POWER MODE to save the change. The calibration gas value stops
flashing and the unit returns to the channel selection screen.
11 . Repeat Step 7 through Step 10 for any other channels that need to be changed.
12 . Use AIR to place the cursor next to ESCAPE.
13 . Press and release POWER MODE. The instrument returns to the SETTING CAL--P
menu item in the Auto Cal Menu.
14 . Use AIR to place the cursor next to ESCAPE.
15 . Press and release POWER MODE. The instrument returns to the GAS CAL menu.
16 . See “Exiting the GAS CAL Menu” on page 75 to return to User Mode.
Making Cylinder Selections in CYL SETTING
The CYL SETTING menu item allows you to group gases together for calibration. As
shipped from the factory, the standard 4 gases (combustible gas, O2, H2S, CO) are assigned to
Cylinder A which means all 4 gases are calibrated at once. As shipped from the factory, the
hydrogen-compensated CO and toxic gases are assigned to Cylinder D or Cylinder E. There
are 5 cylinder assignments available: A, B, C, D, and E. To calibrate each gas separately,
assign each gas to a different cylinder (ie. Cylinder A: combustible gas, Cylinder B: O2,
8 .Press and release POWER MODE. The current setting flashes. In the example below, the
MAINTE 7:49
A
CH4 %LEL
CYL SETTING
MAINTE 7:49
GAS CAL
CAL SETTING
BUMP SETTING
USER MODE
MAINTE 7:49
CAL REMINDER
CAL INTERVAL
CAL EXPIRED
CAL SETTING
combustible gas channel is selected.
9 .Use AIR to change the cylinder assignment. The choices are A, B, C, D, and E.
10 . Press and release POWER MODE to save the change. The cylinder assignment stops
flashing and the unit returns to the channel selection screen.
11 . Repeat Step 7 through Step 10 for any other channels that need to be changed.
12 . Use AIR to place the cursor next to ESCAPE.
13 . Press and release POWER MODE. The instrument will return to the CYL SETING
menu item in the Auto Cal Menu.
14 . Use AIR to place the cursor next to ESCAPE.
15 . Press and release POWER MODE to return to the GAS CAL menu.
16 . See “Exiting the GAS CAL Menu” on page 75 to return to User Mode.
Exiting the GAS CAL Menu
1 .While in the GAS CAL menu, press AIR to scroll to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to the GAS CAL menu item
in User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to enter
Measuring Mode.
Setting Calibration Parameters (CAL SETTING)
The CAL SETTING menu item has 5 items: CAL REMINDER, CAL INTERVAL, CAL
EXPIRED, CAL CHECK GAS, and ESCAPE.
1 .While in User Mode, use AIR to place the cursor next to CAL SETTING.
2 .Press and release POWER MODE. The CAL SETTING menu appears.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 75
ON (factory setting): The GX-3R Pro gives an indication at start up if it is due for calibration.
The type of indication depends on the CAL EXPIRED setting (see pg.76).
OFF: The GX-3R Pro does not give an indication at start up if it is due for calibration.
1 .While in the CAL SETTING menu, use AIR to place the cursor next to CAL
REMINDER.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the CAL SETTING
menu.
5 .See “ESCAPE” on page 77 to return to User Mode.
CAL INTERVAL
This setting defines the amount of time between calibrations. The time can be set in 1 day
increments. The minimum setting is 1 day and the maximum setting is 1000 days. The factory
setting is 90 days.
1 .While in the CAL SETTING menu, use AIR to place the cursor next to CAL
INTERVAL.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the CAL SETTING
menu.
5 .See “ESCAPE” on page 77 to return to User Mode.
CAL EXPIRED
This item defines what indication is given during start up when calibration is due and CAL
REMINDER is set to ON.
CONFIRM TO USE (factory setting): The GX-3R Pro gives an indication at start up if
calibration is past due. Press and release AIR to continue without calibrating or POWER
MODE to perform a calibration.
CANNOT USE: The GX-3R Pro gives an indication at start up if calibration is past due. Press
and release POWER MODE to enter User Mode and perform a calibration. Pressing AIR has
no effect. A successful calibration must be performed in order to use the instrument.
NO EFFECT
desired, press POWER MODE to perform a calibration but it is not necessary to acknowledge
the calibration due indication. The warm-up sequence will continue on its own.
76 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
: The GX-3R Pro gives an indication at startup if calibration is past due. If
www.GlobalTestSupply.com
1 .While in the CAL SETTING menu, use AIR to place the cursor next to CAL
MAINTE 7:49
CAL INTERVAL
CAL EXPIRED
CAL CHECK GAS
CAL SETTING
MAINTE 7:49
CAL EXPIRED
CAL CHECK GAS
ESCAPE
CAL SETTING
EXPIRED.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the CAL SETTING
menu.
5 .See “ESCAPE” on page 77 to return to User Mode.
CAL CHECK GAS
ALL GAS (factory setting): Calibration dates for all gases are used to determine if calibration
is due.
4 GAS
to determine if calibration is due.
1 .While in the CAL SETTING menu, use AIR to place the cursor next to CAL CHECK
: Calibration dates for only the standard 4 gases (combustible gas/O2/H2S/CO) are used
GAS.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the CAL SETTING
menu.
5 .See “ESCAPE” on page 77 to return to User Mode.
ESCAPE
1 .While in the CAL SETTING menu, use AIR to place the cursor next to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 77
The BUMP SETTING menu item has 6 items: BUMP PARAMETERS, BUMP
REMINDER, BUMP INTERVAL, BUMP EXPIRED, BUMP CHECK GAS, and
ESCAPE.
1 .While in User Mode, use AIR to place the cursor next to BUMP SETTING.
2 .Press and release POWER MODE. The BUMP SETTING menu appears.
BUMP PARAMETER
The BUMP PARAMETER menu item has 5 items: GAS TIME, TOLERANCE, CAL
TIME, AUTO CAL, and ESCAPE.
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to BUMP
PARAMETER.
2 .Press and release POWER MODE. The BUMP PARAMETER menu appears.
GAS TIME
The GAS TIME is the amount of time that the instrument is exposed to gas during a bump
test. The available choices are 30 seconds (factory setting), 45 seconds, 60 seconds, and 90
seconds.
1 .While in the BUMP SETTING\BUMP PARAMETER menu, use AIR to place the
cursor next to GAS TIME.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
78 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
4 .Press and release POWER MODE to save the setting and return to the BUMP
MAINTE 7:49
GAS TIME
TOLERANCE
CAL TIME
BUMP PARAMETER
MAINTE 7:49
TOLERANCE
CAL TIME
AUTO CAL
BUMP PARAMETER
PARAMETER menu.
5 .See “ESCAPE” on page 80 to return to the BUMP SETTING menu.
6 .See “ESCAPE” on page 82 to return to User Mode.
TOLERANCE
TOLERANCE is the bump test tolerance value and is represented as a percentage of the
calibration gas concentration. It is the percentage that the bump test reading can differ from
the actual gas concentration. If the bump test reading differs more, the bump test will fail. The
available values are 10%, 20%, 30%, 40%, and 50% (factory setting).
1 .While in the BUMP SETTING\BUMP PARAMETER menu, use AIR to place the
cursor next to TOLERANCE.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
PARAMETER menu.
5 .See “ESCAPE” on page 80 to return to the BUMP SETTING menu.
6 .See “ESCAPE” on page 82 to return to User Mode.
CAL TIME
The CAL TIME is the total time the instrument is exposed to calibration gas when a bump
test fails if AUTO CAL is set to ON. The bump test time is deducted from the calibration
time. For example, if the CAL TIME is set to 90 seconds and the GAS TIME is set to 30
seconds, if the bump test fails, the GX-3R Pro will only be exposed to gas for an additional 60
seconds. The available values are 90 seconds (factory setting), and 120 seconds.
1 .While in the BUMP SETTING\BUMP PARAMETER menu, use AIR to place the
cursor next to CAL TIME.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
PARAMETER menu.
5 .See “ESCAPE” on page 80 to return to the BUMP SETTING menu.
6 .See “ESCAPE” on page 82 to return to User Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 79
ON (factory setting): If a bump test fails, the unit automatically begins a calibration.
OFF: If a bump test fails, the unit does not automatically begin a calibration.
1 .While in the BUMP SETTING\BUMP PARAMETER menu, use AIR to place the
cursor next to AUTO CAL.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
PARAMETER menu.
5 .See “ESCAPE” on page 80 to return to the BUMP SETTING menu.
6 .See “ESCAPE” on page 82 to return to User Mode.
ESCAPE
1 .While in the BUMP SETTING\BUMP PARAMETER menu, use AIR to place the
cursor next to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to the BUMP
PARAMETER menu.
BUMP REMINDER
ON: The GX-3R Pro gives an indication at start up if it is due for bump testing. The type of
indication depends on the BUMP EXPIRED setting (see pg.81).
(factory setting): The GX-3R Pro does not give an indication at start up if it is due for
OFF
bump testing.
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to BUMP
REMINDER.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
SETTING menu.
5 .See “ESCAPE” on page 82 to return to User Mode.
80 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
BUMP INTERVAL
BUMP EXPIRED
BUMP CHECK GAS
BUMP SETTING
This setting defines the amount of time between bump tests. The time can be set in 1 day
increments. The minimum setting is 0 days and the maximum setting is 30 days. The factory
setting is 30 days.
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to BUMP
INTERVAL.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
SETTING menu.
5 .See “ESCAPE” on page 82 to return to User Mode.
BUMP EXPIRED
This item defines what indication is given during start up when a bump test is due and BUMP
REMINDER is set to ON.
CONFIRM TO USE (factory setting): The GX-3R Pro gives an indication at start up if a
bump test is past due. Press and release AIR to continue without bump testing or POWER
MODE to perform a bump test.
CANNOT USE: The GX-3R Pro gives an indication at start up if a bump test is past due.
Press and release POWER MODE to enter User Mode and perform a bump test. Pressing AIR
has no effect. A successful bump test must be performed in order to use the instrument.
NO EFFECT: The GX-3R Pro gives an indication at startup if a bump test is past due. If
desired, press POWER MODE to perform a bump test but it is not necessary to acknowledge
the bump test due indication. The warm-up sequence will continue on its own.
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to BUMP
EXPIRED.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
SETTING menu.
5 .See “ESCAPE” on page 82 to return to User Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 81
ALL GAS (factory setting): Bump test dates for all gases are used to determine if bump test is
due.
4 GAS: Bump test dates for only the standard 4 gases (combustible gas/O2/H2S/CO) are used
to determine if bump test is due.
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to BUMP
CHECK GAS.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the BUMP
SETTING menu.
5 .See “ESCAPE” on page 82 to return to User Mode.
ESCAPE
1 .While in the BUMP SETTING menu, use AIR to place the cursor next to ESCAPE.
2 .Press and release POWER MODE. The instrument will return to User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Adjusting Man Down and Panic Settings (MAN DOWN)
The MAN DOWN menu item has 4 items: MAN DOWN, PANIC, MAN DOWN TIME,
and ESCAPE.
1 .While in User Mode, use AIR to place the cursor next to MAN DOWN.
82 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
2 .Press and release POWER MODE. The MAN DOWN menu appears.
MAINTE 7:49
MAN DOWN
PANIC
MAN DOWN TIME
MAN DOWN MENU
MAINTE 7:49
MAN DOWN
PANIC
MAN DOWN TIME
MAN DOWN MENU
MAINTE 7:49
MAN DOWN
PANIC
MAN DOWN TIME
MAN DOWN MENU
Turning Man Down On/Off
ON: The Man Down alarm is triggered if the instrument detects no motion for the period of
time defined in WARNING 1 TIME, WARNING 2 TIME, and ALARM TIME below.
OFF
(factory setting): The Man Down alarm is not triggered.
1 .While in the MAN DOWN menu, use AIR to place the cursor next to MAN DOWN.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the MAN DOWN
menu.
5 .See “ESCAPE” on page 85 to return to User Mode.
Turning Panic On/Off
ON: A Panic Alarm can be initiated by firmly tapping the instrument twice in a row.
OFF (factory setting): A Panic Alarm cannot be initiated.
1 .While in the MAN DOWN menu, use AIR to place the cursor next to PANIC.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the MAN DOWN
menu.
5 .See “ESCAPE” on page 85 to return to User Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 83
Setting the Man Down Warning/Alarm Times (MAN DOWN TIME)
MAINTE 7:49
PANIC
MAN DOWN TIME
ESCAPE
MAN DOWN MENU
For all settings:
1) AIR to adjust
2) POWER MODE
to save and
MAINTE 7:49
60 SEC
WARNING 1 TIME
MAINTE 7:49
PANIC
MAN DOWN TIME
ESCAPE
MAN DOWN MENU
MAINTE 7:49
90 SEC
ALARM TIME
continue
MAINTE 7:49
75 SEC
WARNING 2 TIME
The Man Down Warning/Alarm times are the amount of time that has to pass between a Man
Down detection and each warning/alarm. They can be set in 1 second increments from 10 120 seconds. When setting the Man Down Warning/Alarm times, keep in mind that ALARM
TIME WARNING 2 TIME WARNING 1 TIME.
Table 16: Man Down Warning Alarm Time Factory Settings
Warning/AlarmFactory Setting
WARNING 1 TIME60 seconds
WARNING 2 TIME75 seconds
ALARM TIME90 seconds
1 .While in the MAN DOWN menu, use AIR to place the cursor next to MAN DOWN
TIME.
2 .Press and release POWER MODE. The current WARNING 1 TIME setting flashes.
3 .Use AIR to adjust the WARNING 1 TIME.
4 .Press and release POWER MODE to save the setting.
5 .Repeat Step 3 and Step 4 for the WARNING 2 TIME and ALARM TIME settings.
6 .The instrument returns to the MAN DOWN menu.
84 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
7 .See “ESCAPE” on page 85 to return to User Mode.
www.GlobalTestSupply.com
ESCAPE
MAINTE 7:49
MAN DOWN
ALARM SETTING
LUNCH BREAK
USER MODE
MAINTE 7:49
- - - -
CH4 %LEL
ALARM SETTING
1 .While in the MAN DOWN menu, press AIR to scroll to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Alarm Settings (ALARM SETTING)
The ALARM SETTING menu item has 3 items: ALARM SETTING, DEFAULT ALM-P,
and ESCAPE.
1 .While in User Mode, use AIR to place the cursor next to ALARM SETTING.
2 .Press and release POWER MODE. The first channel displays.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 85
5 .Press and release POWER MODE to save the setting.
MAINTE 7:49
DEFAULT ALM--P
MAINTE 7:49
ALARM SETTING
LUNCH BREAK
CONFIRMATION
USER MODE
6 .Repeat Step 4 and Step 5 for the Alarm, Alarm H, STEL (CO, H2S, CO2, and super toxic
only) and TWA (CO, H2S, CO2, and super toxic only) settings.
7 .The instrument returns to the ALARM SETTING menu.
8 .Repeat Step 1 - Step 7 to change the alarm points for other channels.
9 .See “ESCAPE” on page 88 to return to User Mode.
Defaulting the Alarm Points
Defaulting the alarm points defaults them back to factory settings as outlined in Table 1 on
page 8 or to the settings saved in the SAVE ALARM-P menu item in Gas Select Mode if you
have performed a SAVE ALARM-P operation.
1 .While in the ALARM SETTING menu, press AIR to scroll to DEFAULT ALM--P.
2 .Press POWER MODE to enter the DEFAULT ALM--P menu item.
3 .Press POWER MODE to perform an alarm default. Press AIR to return to the
DEFAULT ALM--P menu item.
4 .The instrument asks if you’re sure you want to default the alarm points. Press POWER
MODE to default the alarm points. Press AIR to return to the ALARM SETTING
menu.
5 .See “ESCAPE” on page 88 to return to User Mode.
ESCAPE
1 .While in the ALARM SETTING menu, press AIR to scroll to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Updating the Lunch Break Setting (LUNCH BREAK)
OFF (factory setting): The GX-3R Pro automatically starts new TWA and PEAK reading
collection and resets the time in operation at startup.
ON: The Lunch Break Screen displays during startup. From this screen, you can choose to
continue accumulating TWA and PEAK readings and the time in operation from the last time
the GX-3R Pro was used or start collecting new readings and reset the time in operation.
1 .While in User Mode, use AIR to place the cursor next to LUNCH BREAK.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
88 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
4 .Press and release POWER MODE to save the setting and return to User Mode.
MAINTE 7:49
LUNCH BREAK
CONFIRMATION
AUTO BACKLIGHT
USER MODE
MAINTE 7:49
BEEP SELECT
BEEP INTERVAL
ESCAPE
CONFIRMATION
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Setting the Confirmation Beep and Non-Compliance
Indicator (CONFIRMATION)
The CONFIRMATION menu item has 3 items: BEEP SELECT, BEEP INTERVAL, and
ESCAPE.
1 .While in User Mode, use AIR to place the cursor next to CONFIRMATION.
2 .Press and release POWER MODE to enter the Confirmation Menu.
BEEP SELECT
BEEP SELECT defines what kind of confirmation or non-compliance indication you want to
occur in Measuring Mode. The available choices are:
OFF (factory setting): The GX-3R Pro does not provide a confirmation alert or noncompliance indicator.
LED: The GX-3R Pro’s LEDs double flash as often as defined by the BEEP INTERVAL
parameter to verify that the instrument is operating.
BUZZER: The GX-3R Pro’s buzzer double beeps as often as defined by the BEEP
INTERVAL parameter to verify that the instrument is operating.
LED+BUZZER
as defined by the BEEP INTERVAL parameter to verify that the instrument is operating.
BUMP/CAL: If a bump test or a calibration is due and if BUMP EXPIRED or CAL
EXPIRED is set to CONFIRM TO USE or NO EFFECT, the GX-3R Pro’s LEDs double
flash as often as defined by the BEEP INTERVAL parameter to indicate a non-compliance.
Once a successful bump test or calibration (depending on which is due) is done, the LEDs stop
flashing.
ALARM ALERT: If the instrument goes into any gas alarm, the LEDs double flash as often
as defined by the BEEP INTERVAL parameter to indicate a non-compliance. Once a
successful bump test or calibration is done, the LEDs stop flashing.
NOTE:Depending on the Need to get Bump Log setting (only accessed via SDM-3R
program), a data download may also be needed to clear the non-compliance.
: The GX-3R Pro’s LEDs double flash and the buzzer double beeps as often
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 89
BUMP/CAL/ALARM: The LEDs double flash to indicate a non-compliance if any of the
MAINTE 7:49
BEEP SELECT
BEEP INTERVAL
ESCAPE
CONFIRMATION
MAINTE 7:49
BEEP SELECT
BEEP INTERVAL
ESCAPE
CONFIRMATION
following happens.
a. BUMP EXPIRED is set to CONFIRM TO USE or NO EFFECT and a bump test
is due (cleared by successful bump test).
b. CAL EXPIRED is set to CONFIRM TO USE or NO EFFECT and a calibration is
due (cleared by successful calibration).
c. The instrument goes into any gas alarm (cleared by successful bump test or
calibration).
NOTE:Depending on the Need to get Bump Log setting (only accessed via SDM-3R
program), a data download may also be needed to clear the gas alarm noncompliance.
1 .While in the CONFIRMATION menu, use AIR to place the cursor next to BEEP
SELECT.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the Confirmation
Menu.
5 .See “ESCAPE” on page 91 to return to User Mode.
BEEP INTERVAL
The BEEP INTERVAL parameter defines how often the confirmation alert or non-
compliance indicator selected in BEEP SELECT occurs. This setting only applies if the BEEP SELECT parameter is set to something other than OFF. The available choices are 0.5
minutes and 1-99 minutes in 1 minute increments. The factory setting is 5 minutes.
1 .While in the CONFIRMATION menu, use AIR to place the cursor next to BEEP
INTERVAL.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to the Confirmation
Menu.
5 .See “ESCAPE” on page 91 to return to User Mode.
90 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
CONFIRMATION
AUTO BACKLIGHT
BACKLIGHT TIME
USER MODE
MAINTE 7:49
AUTO BACKLIGHT
BACKLIGHT TIME
KEY TONE
USER MODE
1 .While in the CONFIRMATION menu, use AIR to place the cursor next to ESCAPE.
2 .Press and release POWER MODE. The instrument returns to User Mode.
3 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Auto Backlight in Low Light (AUTO BACKLIGHT)
The GX-3R Pro has a luminescence sensor that allows the instrument to detect how bright an
environment is.
ON (factory setting): The instrument’s backlight automatically turns on in a low light
environment.
OFF: The instrument’s backlight does not automatically turn on in a low light environment.
1 .While in User Mode, use AIR to place the cursor next to AUTO BACKLIGHT.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Updating the Backlight Time (BACKLIGHT TIME)
This setting defines how long the LCD backlight stays on when you press any button. The
minimum setting is OFF; the maximum setting is 255 seconds. The factory setting is 30
seconds.
1 .While in User Mode, use AIR to place the cursor next to BACKLIGHT TIME.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 91
ON (factory setting): The instrument will beep when a button is pressed.
OFF: The instrument will not beep when a button is pressed.
1 .While in User Mode, use AIR to place the cursor next to KEY TONE.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Display Mode Items (D MODE SETTING)
OFF: HC GAS LIST, USER ID, STATION ID, INVERT SELECT, LCD
BACKGROUND, BLUETOOTH, BUZZER VOLUME, and LANGUAGE items do not
appear in Display Mode.
ON (factory setting): HC GAS LIST, INVERT SELECT, LCD BACKGROUND,
BLUETOOTH, BUZZER VOLUME, and LANGUAGE items appear in Display Mode.
USER ID and STATION ID screens appear in Display Mode if ID DISPLAY in
Maintenance Mode is also set to ON (factory setting is OFF).
1 .While in User Mode, use AIR to place the cursor next to D MODE SETTING.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
92 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
D MODE SETTING
IR UNIT SELECT
CO2AIR SETTING
USER MODE
This menu item only appears if DISP ZERO SUP is set to ON in Maintenance Mode.
The ZERO SUPPRESS setting is not intended for field adjustment. The default setting for
each sensor is ON.
Sensor
Combustible
Gas
O
2
S0.3 ppm
H
2
CO2 ppm
CO
2
HCN0.5 ppm
NH
3
NO
2
PH
3
SO
2
Zero Suppression
Va lu e
2% LEL
0.5% volume
0 ppm
4 ppm
0.30 ppm
0.02 ppm
0.20 ppm
Turning Zero Follower On/Off (ZERO FOLLOWER)
This menu item only appears if DISP ZERO FLWR is set to ON in Maintenance Mode.
The ZERO FOLLOWER setting is not intended for field adjustment. The oxygen channel
does not support zero follower functionality. The default setting is ON for all other channels.
Reading Units for IR Sensor (IR UNIT SELECT)
This menu item only appears if a CO2 sensor is installed. IR UNIT SELECT changes the IR
sensor’s units.
vol%: CO2 readings displayed in percent volume
ppm: CO2 readings displayed in parts per million
1 .While in User Mode, use AIR to place the cursor next to IR UNIT SELECT.
2 .Press and release POWER MODE. The current setting flashes.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 93
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
CO2 Fresh Air Adjustment On/Off (CO2AIR SETTING)
This menu item only appears if a CO2 sensor is installed.
ON: CO2 channel is set to 400 ppm (0.04% volume) during a demand zero, auto zero, or AIR
CAL.
OFF (factory setting): CO2 channel is not adjusted during a demand zero, auto zero, or AIR
CAL.
1 .While in User Mode, use AIR to place the cursor next to CO2AIR SETTING.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Setting the Date/Time (DATE)
1 .From the main menu, use AIR to place the cursor next to DATE.
2 .Press and release POWER MODE. The date and time display with the year flashing.
3 .Use AIR to display the desired year.
4 .Press and release POWER MODE to save the setting. The month setting flashes.
5 .Repeat Step 3 and Step 4 to enter the month, day, hours, and minutes settings. The date
and time are saved and the instrument returns to User Mode.
94 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
1 .While in User Mode, use AIR to place the cursor next to DATE FORMAT.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Changing the Instrument Language (LANGUAGE)
The available languages for the GX-3R Pro are: English (factory setting), Japanese, Italian,
Spanish, German, French, Portuguese, Russian, Korean, and Chinese (TC).
If you change the language to anything other than English, the LANGUAGE screen appears
in Display Mode, allowing you to change the instrument language back to English.
1 .While in User Mode, use AIR to place the cursor next to LANGUAGE.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .Press and release POWER MODE to save the setting and return to User Mode.
5 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
GX-3R Pro Operator’s ManualChapter 5: User Mode and Calibration • 95
ON: The GX-3R Pro prompts you for a password when you enter User Mode. The factory-set
password is 0405 but it can be changed as desired.
OFF (factory setting): No password is required to enter User Mode.
1 .While in User Mode, use AIR to place the cursor next to USER PASSWORD.
2 .Press and release POWER MODE. The current setting flashes.
3 .Use AIR to display the desired setting.
4 .If you selected OFF, press and release POWER MODE to save the setting and return to
the USER PASSWORD item in User Mode.
If you selected ON, continue with Step 5.
5 .Press and release POWER MODE. The Set Password Screen appears. The current
password displays and the first digit flashes.
6 .Use AIR to display a number from 0 to 9.
7 .Press and release POWER MODE to enter the selection and advance to the next number.
To go back a number, press and hold AIR and POWER MODE for a few seconds.
8 .Repeat Step 6 and Step 7 to select the remaining numbers. When you press and release
POWER MODE to enter the last number, the password is saved and you return to User
Mode.
9 .See “Returning to Measuring Mode (START MEASURE)” on page 98 to return to
Measuring Mode.
Viewing the ROM/SUM (ROM/SUM)
The ROM/SUM screen shows the instruments’ firmware version and firmware checksum.
1 .While in User Mode, use AIR to place the cursor next to ROM/SUM.
96 • Chapter 5: User Mode and CalibrationGX-3R Pro Operator’s Manual
This chapter describes troubleshooting procedures for the GX-3R Pro. It also includes
procedures for instrument cleaning, replacing and recharging the batteries, and replacing
various consumable parts.
WARNING:RKI Instruments, Inc. recommends that service, calibration, and repair of
RKI Instruments be performed by personnel properly trained for this work.
Replacing sensors and other parts with original equipment does not affect
the intrinsic safety of the instrument.
Troubleshooting
The troubleshooting table describes error messages, symptoms, probable causes, and
recommended action for problems you may encounter with the GX-3R Pro.
Table 17: Troubleshooting the GX-3R Pro
SymptomsProbable CausesRecommended Action
• The LCD is blank.• The unit may have been turned
off.
• The batteries may need to be
replaced or recharged.
• The LCD shows
abnormally high or
low readings but other
gas detection
instruments do not.
• One of the sensor’s filters may
need to be replaced.
• The GX-3R Pro may need to be
recalibrated.
• The sensor for the affected
channel(s) may need
replacement.
1. To turn on the unit, press and briefly
hold POWER MODE.
2. If the unit does not turn on, replace or
recharge the batteries.
3. If the difficulties continue, contact RKI
Instruments, Inc. for further instruction.
1. Replace the sensor filter.
2. Recalibrate the unit.
3. If the difficulties continue, replace the
sensor for the affected channel(s) and
calibrate the affected channel(s).
4. If the difficulties continue, contact RKI
Instruments, Inc. for further instruction.
GX-3R Pro Operator’s ManualChapter 6: Maintenance • 99
• Calibration fails. • The calibration values may not
match the cylinder gas
concentrations.
• The charcoal filter or charcoal
half of the dual filter is
saturated causing an elevated
CO reading.
• The sample gas is not reaching
the sensors because of a bad
connection.
• The calibration cylinder may be
out of gas or is outdated.
• The sensor for the affected
channel(s) may need
replacement.
• Heart symbol at the
top of the screen
becomes steadily on or
disappears
• Charge LED alternates
between green and
orange
• A microprocessor error has
occurred.
• Charging environment is
outside the allowed 0 - 40°C
charging temperature range.
1. Make sure the GX-3R Pro has been
properly set up for calibration.
2. Change the charcoal filter or dual filter.
3. Check all calibration tubing for leaks or
for any bad connections.
4. Verify that the calibration cylinder
contains an adequate supply of fresh test
sample.
5. If the fail condition continues, replace
the sensor(s).
6. If the difficulties continue, contact RKI
Instruments, Inc. for further instruction.
• Contact RKI Instruments, Inc. for further
instruction.
• Move the charger to a location that is
within the allowed 0 - 40°C charging
temperature range.
Instrument Cleaning
Clean the GX-3R Pro with a cloth dampened with water if it becomes excessively dirty. Do
not use alcohol or other cleaning solvents.
Replacing the Batteries (Alkaline Version)
NOTE:Use Duracell MN2400 or PC2400 alkaline batteries or RKI Instruments, Inc.
lithium-ion battery pack 49-1625 to maintain the CSA classification of the GX-3R
Pro. Use of other batteries will void the CSA classification and may void the
warranty. Do not mix old/new or different types of batteries.
NOTE:Utiliser Procell 2400 piles alcalines ou RKI Instruments, Inc. pack batterie lithium-
ion 49-1625 de maintenir la classification CSA de la GX-3R Pro. L’utilisation
d’autres piles annule la classification CSA et peut annuler la garantie. Ne mélangez
pas les anciennes/nouvelles ou différents types de piles.
CAUTION:Sensors, filters, and alkaline batteries are the only user-serviceable parts in
the GX-3R Pro. Do not replace or modify any other part.
10 0 • Chapter 6: Mainten anceGX-3R Pro Operator’s Manual