Read and understand this instruction manual before
operating instrument. Improper use of the gas monitor could
result in bodily harm or death.
Periodic calibration and maintenance of the gas monitor is
essential for proper operation and correct readings. Please
calibrate and maintain this instrument regularly! Frequency
of calibration depends upon the type of use you have and
the sensor types. Typical calibration frequencies for most
applications are between 1 and 3 months, but can be
required more often or less often based on your usage.
RKI Instruments, Inc. warrants the GX-2009 sold by us to be free from defects in
materials, workmanship, and performance for a period of two years from the date of
shipment from RKI Instruments, Inc. This includes the instrument and the original
sensors. Replacement parts are warranted for 1 year from the date of their shipment
from RKI Instruments, Inc except for sensors which are warranted for 2 years. Any
parts found defective within their warranty period will be repaired or replaced, at our
option, free of charge. This warranty does not apply to those items which by their
nature are subject to deterioration or consumption in normal service, and which must
be cleaned, repaired, or replaced on a routine basis. Examples of such items are:
Warranty is voided by abuse including mechanical damage, alteration, rough handling,
or repair procedures not in accordance with the instruction manual. This warranty
indicates the full extent of our liability, and we are not responsible for removal or
replacement costs, local repair costs, transportation costs, or contingent expenses
incurred without our prior approval.
REPRESENTATIONS, EXPRESSEDORIMPLIED, ANDALLOTHEROBLIGATIONSORLIABILITIESONTHE
PA RTOF RKI INSTRUMENTS, INC. INCLUDINGBUTNOTLIMITEDTOTHEWA RR A N T YOF
MERCHANTABILITYORFITNESSFORAPARTICULARPURPOSE. INNOEVENTSHALL RKI
I
NSTRUMENTS, INC. BELIABLEFORINDIRECT, INCIDENTAL, ORCONSEQUENTIALLOSSORDAMAGE
OFANYKINDCONNECTEDWITHTHEUSEOFITSPRODUCTSORFAI LURE OFITSPRODUCTSTO
FUNCTIONOROPERATEPROPERLY.
This warranty covers instruments and parts sold to users only by authorized
distributors, dealers, and representatives as appointed by RKI Instruments, Inc.
We do not assume indemnification for any accident or damage caused by the operation
of this gas monitor and our warranty is limited to replacement of parts or our complete
goods.
WARNING: Understand manual before operating. Substitution of components
may impair intrinsic safety. To prevent ignition of a hazardous
atmosphere, batteries must only be changed or charged in an area
known to be nonhazardous. Not tested in oxygen enriched
atmospheres (above 21%).
NOTE: RKI Instruments, Inc. recommends that you refer to ISA-RP12.13, Part II-
1987 or an equivalent international recommended practice for guidance in
the use of combustible gas detection instruments.
Using an advanced detection system consisting of four gas sensors, the GX-2009 personal
four-gas monitor detects the presence of combustible gas, oxygen (O2), carbon monoxide
(CO), and hydrogen sulfide (H2S) simultaneously. The GX-2009’s compact size and easy-touse design makes 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-2009 offers a
full range of features, including:
•Simultaneous four-gas monitoring and display of combustible gases, O2, CO, and H2S
•Backlit LCD (liquid crystal display) for complete and understandable information at a
glance
•Distinctive audible/vibrating alarms for dangerous gas conditions and audible alarms for
unit malfunction
•Microprocessor control for reliability, ease of use, and advanced capabilities
•Resistance to RF (radio frequency) interference
•Datalogging including interval trend data and alarm trend data
•STEL/TWA and over range alarm display
•Peak hold readouts
•Built-in time function
•Lightweight and compact high impact plastic case
•Rotatable alligator clip for “hands-free” gas monitoring, belt clip optional
•CSA classified for Class I, Division I, Groups A, B, C, and D hazardous atmospheres
WARNING: The GX-2009 detects oxygen deficiency and elevated levels of oxygen,
combustible gases, carbon monoxide, and hydrogen sulfide, all of which can
be dangerous or life threatening. When using the GX-2009, 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-2009 as described in this manual.
NOTE: Only the combustible gas detector portion of this instrument has been assessed for
*The GX-2009 is also available set up for general hydrocarbons and calibrated to a combustible gas other than
methane, such as isobutane. Consult RKI Instruments, Inc. for further information.
Dimensions: 2.7 H, 3.0 W, 1.0 D inches
Approx. 70 H, 75 W, 25 D mm
Weight: 4.6 oz.
NOTE: The bump test function in Calibration Mode is included in instruments with
firmware version 03955 or later installed. See page 44 for a description of the bump
test function. GX-2009 instruments shipped after May 2011 include the bump test
function. Instruments that have a serial number starting with 04516 or later shipped
from the factory with the bump test function available. Instruments that have a serial
number starting with 04515 did not include the bump test function when shipped
from the factory. The factory setting for the bump test function is off.
This section describes the GX-2009’s components and the charging station. These
components include the GX-2009’s case, alligator and belt clips, sensor retainer, sensor
retainer gasket, sensor cover retainer, scrubber filters, sensor cover, sensors, LCD, control
buttons, printed circuit boards, alarm LED arrays, buzzer, vibrator, batteries, and charging
station.
The GX-2009’s sturdy, high-impact plastic case is suitable for use in many environmental
conditions, indoors and out. The unit is dust proof and water resistant. Rubber overmolded
surfaces on much of the case help protect it from impact damage and aid in holding the
instrument in your hand.
A clear plastic window through which the LCD can be viewed is located on the front of the
case. Three brass charging contacts that are used when the GX-2009 is placed in the charging
station are on the back of the case. Four sensor diffusion ports are located on the bottom of the
case. The ports are labelled as follows from left to right: H2S, CO, HC, and O2. Three frosted
windows, one on the left side, one of the right side, and one on top, cover alarm LED arrays.
There are two buzzer sound openings, one on the front below the LCD and one on the top
behind the top LED array. An IR (infrared) communication port is located on the top left side
which is used to transfer information when the instrument is used with one of the calibration
or downloading accessories.
There are three threaded inserts on the back of the case. These are used to mount the alligator
clip or the optional belt clip.
The GX-2009 is available with two types of clips, the standard alligator clip and the optional
belt clip. Both are illustrated in Figure 3.
The alligator clip can be used to attach the GX-2009 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 how
the instrument is oriented when worn. The belt clip is used to easily clip the GX-2009 on a
belt.
The sensor retainer holds the gas sensors in place and snaps onto the bottom of the case. It has
4 diffusion ports, one for each sensor, and has recessed areas in it for the charcoal filter, and
the H2S removal filters. It also has indexing features for the sensor retainer gasket. The sensor
retainer gasket seats onto the sensor retainer and seals the interface between the sensor
retainer, sensor cover, and sensor cover retainer. The sensor cover retainer snaps onto the
sensor retainer. Two screws secure the sensor retainer and the sensor cover retainer to the case.
Scrubber Filters/Sensor Cover
Charcoal Filter Disk
The charcoal filter disk is located in the CO sensor diffusion port of the sensor retainer. It is
black, has a woven texture, and is impregnated with an H2S absorbing material. It fits into a
recessed area of that port. The CO sensor will respond if exposed to H2S and certain
hydrocarbon gasses. The charcoal filter scrubs these gasses out of the gas sampled to avoid
false CO readings. The H
S absorbing material added to the charcoal filter extends it’s H2S
absorbing life. If false CO readings are noticed, especially high readings in the presence of
S, change the charcoal filter disk.
H
2
H2S Removal Filter Disks
One H2S removal filter disk is located in a recessed area of the combustible gas sensor
diffusion port in the sensor retainer. It prevents H2S in the ambient air from reaching the unit’s
combustible gas sensor. Removing H2S that is present in the monitored air prolongs the life of
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 can absorb H2S for 33 ppm
hours and should be replaced after that much exposure. With this many ppm hours of
absorption, the H2S filter disk should be replaced after 80 minutes of exposure to 25 ppm H2S.
This equates to replacing the H2S filter disk after 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.
Sensor Cover
The sensor cover is white and protects the scrubber filters and sensors from dust and water. It
fits on the sensor retainer gasket over all the sensor diffusion ports and is secured in place by
the sensor cover retainer. If the sensor cover becomes dirty, the response time and accuracy of
the GX-2009 will be affected. Replace the sensor cover if it appears dirty.
Sensors
The GX-2009 uses four sensors to monitor combustible gases, O2, CO, and H2S
simultaneously. The sensors are protected from the environment by the sensor cover which
allows ambient air to diffuse to the sensors. The sensors use different detection principles, as
described below.
Combustible Gas (LEL) Sensor
The combustible gas sensor detects combustible gas and vapors in the LEL (lower explosive
limit) range with a catalytic element. A sintered metal flame arrestor covers the element and
allows ambient air to diffuse into the sensor. The reaction of gas with oxygen on the catalyst
causes a change in the resistance of the element which affects the current flowing through it.
The current is amplified by the GX-2009’s circuitry, converted to a measurement of
combustible gas concentration, and displayed on the LCD.
CAUTION: Do not expose the combustible 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.
The O2 sensor is a galvanic type sensor. A membrane covers the cell and allows gas to diffuse
into the cell at a rate proportional to the partial pressure of oxygen. The oxygen reacts in the
cell and produces a voltage proportional to the concentration of oxygen. The voltage is
measured by the GX-2009’s circuitry, converted to a measurement of gas concentration, and
displayed on the LCD.
CO and H2S Sensors
The CO and H2S sensors are electrochemical sensors that consist of two precious metal
electrodes in an 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 current is amplified by the GX-2009’s
circuitry, converted to a measurement of gas concentration, and displayed on the LCD.
LCD
The LCD (liquid crystal display) is visible through the GX-2009’s front window. Target gas
concentrations, the time, battery condition, and alarm indications are displayed on the LCD.
When either of the control buttons are pressed, the LCD backlight comes on for 30 seconds.
Control Buttons
Two control buttons are located below the display on either side of the front buzzer opening.
The AIR button is on the left and the POWER MODE button is on the right. The functions
performed by the control buttons are summarized in the following table:
Table 2: GX-2009 Control Buttons
Button Function
•Turns the unit on and off
•Turns the LCD back light on
•Scrolls through Display Mode
•Resets the alarm circuit (gas alarms)
POWER MODE
AIR
•Enters Calibration Mode with the AIR button
•Enters User Setup Mode with the AIR button
•Selects a displayed item
•Saves adjusted parameters
•Selects displayed parameters
•Turns the LCD back light on.
•Performs a fresh air adjustment
•Enters Calibration Mode with the MODE POWER button.
•Enters User Setup Mode with the MODE POWER button.
The primary function of the GX-2009’s printed circuit boards is to amplify the signal sent to
them from the four gas sensors, convert the signal to a measurement of gas concentration,
display the gas concentration on the LCD, store peak, STEL, and TWA readings, and activate
the alarm circuit if an alarm point has been reached. They monitor battery level, battery
failure, and sensor failure. They also control the GX-2009’s time function and various
operating modes.
NOTE: The printed circuit boards contain no user serviceable parts.
Alarm LED Arrays
Three red alarm LED (light emitting diode) arrays are visible through frosted plastic lenses in
the case. One is on the top, one on the left side, one on the right side of the case. The alarm
LED arrays alert you to gas, low battery, and failure alarms.
Buzzer & Vibrator
A solid-state electronic buzzer is mounted inside the GX-2009’s case. The buzzer sounds for
gas alarms, failure alarms, and as an indicator during normal use of the GX-2009’s various
operating modes.
A vibrating motor inside the GX-2009 case vibrates for gas alarms and as an indicator during
normal use of the GX-2009’s various operating modes.
NiMH Batteries
Two NiMH (nickel metal hydride) batteries, each with an integral holder, supply 2.4 volts to
power the GX-2009. The batteries will run the unit for up to 20 hours when no alarms have
been activated during that time period. The batteries are designed to be charged while in the
GX-2009 with the GX-2009 Charging Station. The batteries should not be removed from the
GX-2009 unless they need to be replaced because they will no longer hold a charge. The
battery icon in the lower left corner of the LCD shows the charge remaining in the batteries.
See “Recharging the GX-2009’s NiMH Batteries” on page 57 for instructions to recharge the
batteries and “Replacing the GX-2009’s NiMH Batteries” on page 60 for instructions to
replace the batteries.
Figure 4: GX-2009 Charging Station, Single Instrument Station
Charging Station
The GX-2009’s NiMH batteries are charged with the GX-2009 Charging Station. There are
two types of charging stations available, the standard AC powered charging station and the
optional vehicle plug DC powered charging station.
AC Powered Charging Station
The standard AC powered charging station is available in configurations that charge from one
to five instruments at a time. The single instrument charging station consists of one instrument
charging base and an AC adapter. The AC adapter for the standard charging station plugs into
a 115 VAC wall outlet and connects to the charging station with a jack on the end of a five foot
DC output cable. The AC adapter will also work for 100 VAC or 220 VAC if an appropriate
plug adapter is provided. The single instrument AC charging station is shown in Figure 4.
Figure 5: GX-2009 Charging Station, Two Instrument Station
Adapter Jack
AC Adapter
Figure 6: GX-2009 Charging Station, Five Instrument Station
Charging stations for more than one instrument include additional chargers that are attached to
each other. The same AC adapter can power up to a maximum of 5 charging bases. The two
instrument charging station is shown in Figure 5, and the five instrument station is shown in
Figure 6.
An optional DC powered single instrument charging station is available with a vehicle plug 12
VDC adapter. The DC adapter for the charging station can only provide enough power to
charge one instrument at a time, so the DC powered charging station is only available as a
single instrument charging station. It uses the same charging base as the AC powered charging
station.
This section explains how to start up the GX-2009 and get it ready for operation.
Start-up Procedure
1. Press and briefly hold down the POWER MODE button. The backlight will turn on and all
2. The vibrator vibrates and the alarm lights flash momentarily.
3. If Cal. Limit Display is turned on, the screen that appears next depends on how Cal.
the display segments will turn on. Release the button when you hear a beep.
Limit Check is set. These parameters and the Auto Zero Adjustment parameter
mentioned in Step 9 below cannot be set using the GX-2009’s instrument menus, but are
set using the GX-2009 Setup Program. See the GX-2009 Setup Program Operator’s
Manual for information regarding changing various instrument parameters that are not
available for adjustment in the instrument’s operating modes.
•If the unit is due for calibration and Cal. Limit Check is set to Confirm to use, then
the following screen displays.
The alarm LED’s and buzzer will pulse several times. After this, press and release the
POWER MODE button. You will hear a beep and startup sequence will continue.
•If the unit is due for calibration and Cal. Limit Check is set to Can’t use, then the
following screen displays.
The alarm LED’s and buzzer will pulse several times. This screen will then remain on
the display until the unit is turned off. The GX-2009 cannot be used until a complete
calibration has been performed either by selecting AUTO CAL or ONE CAL in the
Calibration Mode menu. See “Performing a Span Adjustment in AUTO CAL” on
page 35 or “Performing a Span Adjustment in ONE CAL” on page 40 for calibration
instructions.
•If calibration is not due or Cal. Limit Check is set to None, then the following screen
appears for a few seconds indicating when the next calibration is due.
NOTE: The following screen only appears if Bump Test Limit Display is set to On using
the User Setup Program. The standard factory setting for this function is Off.
4. If Bump Test Limit Display is set to On using the User Setup Program, the next screen
will depend on how Bump Limit Check is set using the User Setup Program.
•If the unit is due for bump testing and Bump Test Limit Check is set to Confirm to
use, then the following screen displays.
The alarm LED’s and buzzer will pulse several times. After this, press and release the
POWER MODE button. You will hear a beep and startup sequence will continue.
WARNING: You must press the POWER MODE button to continue to normal operation.
If you do not press the POWER MODE button, the buzzer will continue to
beep and the LEDs will continue to flash for 6 seconds every 5 seconds and
the unit will not enter normal operation.
•If the unit is due for bump testing and Bump Test Limit Check is set to Can’t use,
then the following screen displays.
The alarm LED’s and buzzer will pulse several times. This screen will then remain on
the display until the unit is turned off. The GX-2009 cannot be used until a bump test
has been performed. See “Performing a Bump Test in BUMP” on page 44 for bump
test procedures.
WARNING: You must perform a bump test in order to continue to normal operation. If
you do not perform a bump test, the buzzer will continue to beep and the
LEDs will continue to flash for 6 seconds every 5 seconds and the unit will
not enter normal operation.
•If bump testing is not due or Bump Test Limit Check is set to None, then the
08 - 7.27
NEXT BUMP
15 d
08 - 7.27
3:51
bAtt.
2.4
V
AL -- H
F A IL
SENSOR
CO ppm
following screen appears for a few seconds indicating when the next bump test is due.
NOTE: If a successful calibration is performed, the next bump test date is reset and starts
over even though a bump test was not performed.
5. The Date/Time Screen appears for a few seconds.
This screen displays the current date and time.
6. The Battery Voltage/Alarm Pattern Screen appears for a few seconds.
The screen displays the current battery voltage and the alarm pattern. AL -- H indicates
latching alarms and AL -- A indicates self-resetting alarms. See “Alarm Logic/Resetting
Alarms” on page 27 for a description of latching and self-resetting alarms.
7. The display then indicates the following items for about a second each:
•Full scale values for all channels
•Warning setpoint (low gas alarm) for all channels
•Alarm setpoint (high gas alarm) for all channels
•STEL alarm setpoint for the CO and H2S channels
•TWA alarm setpoint for the CO and H2S channels
8. If the GX-2009 experiences a sensor failure during start up, a screen indicating which
sensor failed displays. In the example below, the CO sensor has failed.
If you wish to continue, press and release the POWER MODE button to acknowledge the
failure. The gas reading for the failed sensor will be replaced by “- - -”. Replace the failed
sensor as soon as possible.
9. If Auto Zero Adjustment is set to On, then the GX-2009 will perform an automatic fresh
air adjustment.
If the fresh air adjustment is successful, the unit will proceed to Normal Mode. If one or
more of the sensors fails the fresh air adjustment, the display will indicate which sensor or
sensors failed. If a failure occurs, press and release the POWER MODE button to proceed
to Normal Mode. The gas reading for the failed sensor or sensors will be replaced by “- - ”. Replace any sensors that fail the automatic fresh air adjustment as soon as possible.
WARNING: If the Auto Ze ro Ad justment f eature is tur ned on, make sure that you start-up
the GX-2009 in a known fresh air environment, an environment free of
combustible or toxic gasses and of normal oxygen content, 20.9%. If you do
not start-up the unit in a fresh air environment, the fresh air adjustment will
not be accurate.
10. The GX-2009 is now operating in Measuring Mode and monitoring for gas. The Normal
Operation Screen appears.
The concentrations of the target gasses are displayed along with the time in the lower right
corner and the battery charge level in the lower left corner.
Performing a Fresh Air Adjustment
Before using the GX-2009, set the fresh air reading. Performing this adjustment ensures
accurate gas readings in the monitoring environment as long as the calibration is current.
1. Find a fresh-air environment. This is an environment free of toxic or combustible gasses
and of normal oxygen content (20.9%).
2. With the unit on and in the Normal Operation Screen, press and hold the AIR button. The
LCD displays the following screen prompting you to keep pressing the AIR button.
This section describes the operation of the GX-2009 in Measuring Mode. It explains how
enter Display Mode to view the peak gas readings of the four target gasses, the STEL and
TWA readings for H2S and CO, and the full scale detection range value for each target gas. It
covers important issues regarding combustible gas detection. It also covers alarm indications
and use of the aspirator adapter accessory.
Normal Operation
When the GX-2009 comes out of its startup sequence, see “Start Up” on page 18, it enters
Measuring Mode and is in normal operation if no alarm indications are taking place. It is
advisable to perform a fresh air adjustment when the GX-2009 comes out of its startup
sequence as described in “Start Up”. If Auto Zero Adjustment is set to On, be sure to follow
the guidelines in Step 9 in “Start-up Procedure” on page 18.
In the Normal Operation Screen of Measuring Mode, the battery level, time, and gas
concentrations for each channel are displayed on the LCD. The time is in the lower right
corner and the battery level is in the lower left corner. Combustible gas is displayed as a
percentage of the lower explosive limit (%LEL), oxygen is displayed as a volume percentage
(vol%), H2S and CO as parts per million (ppm). The combustible channel gas name is CH4 if
it is calibrated to methane (CH4) or HC if it is calibrated to a another combustible gas. See
“Combustible Gas Detection” on page 25 for a discussion of the combustible channel gas
name and calibration.
Display Mode
You can access Display Mode while in Measuring Mode by using the POWER MODE button.
In Display Mode you can view and reset the peak readings for each target gas, view the TWA
and STEL values for CO and H2S, and view the detection range full scale for each target gas.
STEL is an acronym for short-term exposure limit, and it is the average reading of the target
gas during the last 15 minutes. TWA is an acronym for time-weighted average, and it is the
average reading for the target gas during the last eight (8) hours. If eight (8) hours has not
elapsed since the unit was turned on, the TWA is still calculated over eight hours, with the
missing time assigned a zero (0) value for the readings. Similarly, if the unit has not been on
for 15 minutes, the missing time is assigned a 0 value and the STEL is calculated over 15
minutes. The peak readings, STEL values, and TWA values are cleared when the unit is turned
off.
To enter Display Mode and view items or reset the peak readings, do the following:
1. Make sure the GX-2009 is in the Measuring Mode Normal Operation screen. The GX2009 must be in the Normal Operation Screen for you to access Display Mode.
2. Press and release the POWER MODE button to enter Display Mode. The backlight will
turn on and the PEAK Screen will appear.
The peak readings since the GX-2009 was turned on are displayed for combustible gas,
CO, and H
3. If you do not want to clear the peak readings, continue to the next step.
If you want to clear the peak readings, press and hold the AIR button. After a couple of
seconds, the LCD will prompt you to hold the AIR button with the following screen.
S. The minimum reading is displayed for oxygen.
2
Hold the AIR button until the following screen appears, then release it.
The peak readings will be cleared and the unit will return to the PEAK Screen.
4. Press and release the POWER MODE button again to proceed to the STEL Screen. The
STEL values for CO and H2S are displayed.
5. Press and release the POWER MODE button again to proceed to the TWA Screen. The
TWA values for CO and H2S are displayed.
6. Press and release the POWER MODE button again to proceed to the Full Scale Screen.
The detection range full scale value for each channel is displayed.
7. Press and release the POWER MODE button again to return to Measuring Mode.
NOTE: If you do not press a button for 20 seconds while in Display Mode, the GX-2009
will return to Measuring Mode automatically and the backlight will turn off 30
seconds since the last button was pressed.
There are three issues that must be considered when monitoring for combustible gas.
•The combustible sensor will respond to any combustible gas. The standard calibration gas
for the GX-2009 combustible channel is methane (CH4). If the instrument is calibrated to
a different combustible gas, such as hexane or propane, the gas name for the combustible
channel may be set to HC by using the GX-2009 Setup Program. See the GX-2009 Setup
Program Operator’s Manual for information on how to set the combustible gas name.
The table below lists the conversion factors for several hydrocarbon gasses if the GX-2009 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 pentane and the display reads 10% LEL
on the combustible channel, you actually have 10% LEL x 1.56 = 15.6% LEL pentane
present.
Table 3: LEL Hydrocarbon Conversions
Gas
Acetone1.79Iso Butane1.47
Acetylene1.92MEK2.27
Benzene2.00Methane1.00
Ethane1.09Methanol1.92
Ethanol2.50Pentane1.56
Ethylene1.06Propane1.35
Heptane2.50Propylene1.32
Hexane2.08Toluene3.13
Hydrogen1.25Xylene4.27
IPA2.78
LEL Conversion
Factor (CH
Cal.)
4
Gas
LEL Conversion
Factor (CH4 Cal.)
•The GX-2009 provides the combustible sensor with some protection against exposure to
high levels of combustible gas. It does this by turning off the combustible sensor power
temporarily when it determines that an over scale (more than 100% LEL) concentration of
combustible gas is present that may damage the sensor. Nevertheless, concentrations of
combustible gas of more than 100% LEL can still affect the zero level or calibration of the
combustible sensor if the concentration is high enough.
CAUTION: Do not expose the combustible 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 followed by a declining or
erratic reading may indicate a gas concentration above the LEL which may be
hazardous.
•Some gases such as silicone vapors, chlorinated hydrocarbons, and sulphur compounds
can contaminate the detection elements inside the combustible sensor damaging the sensor
and resulting in 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.
Alarms
This section covers alarm indications. It also describes the two types of alarm logic, how to
reset the GX-2009 after an alarm has occurred, and how to respond to an alarm condition.
NOTE: False alarms may be caused by radio frequency (RF) or electromagnetic (EMI)
interference. Keep the GX-2009 away from RF and EMI sources such as radio
transmitters or large motors.
Alarm Indications
The GX-2009 will sound an alarm, the LEDs will flash, and the unit will vibrate when one of
the target gas concentrations rises above the Warning (low alarm) setpoint, or in the case of
oxygen falls below the Warning setpoint, for that gas.
The GX-2009 will also sound an alarm, the LEDs will flash, and the unit will vibrate when the
Alarm (high alarm) setpoint is reached for any of the channels and when the STEL and TWA
alarm points are reached for CO and H2S.
When a trouble condition occurs, such as a sensor failure or low battery charge, the alarm
indication will depend on the alarm type.
Table 4 below summarizes the types of alarms produced by the GX-2009.
Table 4: Alarm Types and Indications
Alarm TypeVisual IndicationsOther Indications
Warning (low alarm)
Concentration of gas rises above the
Warning setpoint or falls below the
Warning setpoint for O
2
•WARNING blinks to the right
of the battery level icon
•Reading for the gas in alarm
flashes
•Alarm LEDs flash
•Backlight turns on
•Buzzer sounds alternating
between a low and high
pitch
Alarm (high alarm)
Concentration of gas rises above the
Alarm setpoint
TWA or STEL
Concentration of CO or H2S rises
above the TWA or STEL alarm
point setting
Over Range
Concentration of gas rises above
full scale
•ALARM flashes to the right of
the battery level icon faster than
Warning indication
•Reading for the gas in alarm
flashes faster than Warning
indication
•Alarm LEDs flash faster than
Warning indication
•Backlight turns on
•TWA or STEL flashes to the
right of the battery level icon
•The gas name in alarm flashes
•Alarm LEDs flash
•Backlight turns on
•OVER flashes to the right of the
battery level icon at the same
rate as Alarm indication
•Gas reading replaced by
brackets flashing at the same
rate as Alarm indication
•Alarm LEDs flash at the same
rate as Alarm indication
•Backlight turns on
•Buzzer sounds alternating
between a low and high
pitch faster than Warning
indication
•Vibrator pulses faster than
Warning indication
•Buzzer sounds alternating
between a low and high
pitch at the same rate as
Warning indication
•Vibrator pulses at same rate
as Warning indication
•Buzzer sounds alternating
between a low and high
pitch at same rate as Alarm
indication
•Vibrator pulses at same rate
as Alarm indication
Low Battery Warning•Battery icon blinksNone
Dead Battery Alarm•Gas readings replaced by FAIL
in the upper left corner of LCD
•BATTERY is displayed to the
right of the battery icon.
•Battery icon blinks
•LEDs flash
Sensor Failure•Name of failed sensor or sensors
displayed.
•FAIL is displayed
•LEDs flash
Buzzer pulses
Buzzer sounds a double pulsing
tone
(two pulses in quick
succession)
Alarm Logic/Resetting Alarms
The gas alarm logic can be set to either latching or self resetting with the GX-2009 Setup
Program by setting the Alarm Pattern parameter. See the GX-2009 Setup Program
Operator’s Manual for information on how to set the alarm logic. If Alarm Pattern is set to
Latch, the gas alarms are latching. If Alarm Pattern is set to Reset, the gas alarms are selfresetting. The standard factory setting is Latch for latching alarms.
If the alarms are latching, then an alarm indication will continue even if the gas reading
causing the alarm decreases below the alarm setpoint (increases above for oxygen Warning)
and will continue until the alarm is reset. To be able to reset the alarm, the gas reading that
caused the alarm must decrease below the alarm setpoint (increase above for oxygen Warning)
before that alarm can be reset. To reset latching alarms, press and release the POWER MODE
button after the gas reading falls below the alarm setpoint (or above for oxygen Warning).
If the alarms are self-resetting, then an alarm condition will automatically reset when the gas
reading that caused the alarm decreases below the alarm setpoint (increases above for oxygen
Warning).
If a STEL or TWA alarm has been activated, it cannot be reset. You must turn off the unit to
clear the alarm.
Responding to Alarms
This section describes response to gas, over range, battery, and sensor failure 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. If your unit is set for latching alarms, reset the alarm using the POWER MODE button
once the alarm condition has been cleared.
Responding to Over Range Alarms
WARNING: An over range condition may indicate an extreme combustible gas, toxic gas,
or oxygen content condition. Take immediate action and confirm the gas
levels in the area with a different GX-2009 or with another gas detecting
device.
1. Determine which channel is indicating the alarm.
2. Follow your established procedure for an increasing gas condition.
3. Reset the alarm using the POWER MODE button once the alarm condition has cleared.
4. Calibrate the GX-2009 as described in “Performing a Span Adjustment in AUTO CAL”
on page 35 or “Performing a Span Adjustment in ONE CAL” on page 40.
5. If the over range condition continues, 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.
WARNING: The GX-2009 is not operational as a gas monitoring device during a dead
battery alarm. Take the GX-2009 to a non-hazardous area and recharge the
battery as described in “Recharging the GX-2009’s NiMH Batteries” on
page 57
The GX-2009 is fully functional during a low battery warning. However, depending upon
conditions, the GX-2009 has only two or three hours of operating time left after the low
battery warning has been triggered. Recharge the battery pack as soon as possible as described
in “Recharging the GX-2009’s NiMH Batteries” on page 57.
NOTE: Alarms and the back light feature consume battery power and reduce the amount of
operating time remaining.
Responding to Sensor Failure Alarms
1. Determine which sensor has triggered the sensor failure alarm.
2. Try calibrating the sensor first as described in “Performing a Span Adjustment in AUTO
CAL” on page 35 or “Performing a Span Adjustment in ONE CAL” on page 40 before
replacing it.
3. If the sensor failure continues, replace the sensor as described in “Replacing a Sensor” on
page 64.
4. If the sensor failure condition continues after you have replaced the sensor, contact RKI
Instruments, Inc. for further instructions.
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-2009 does not include
the aspirator adapter.
1. Turn on the GX-2009 as directed in “Start Up” on page 18.
2. Attach the sample adapter plate to the sensor side of the instrument.
3. Screw the probe onto the threaded end of the 10 ft. hose.
4. Attached the 10 ft. 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.
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. To see the
maximum readings for each channel, display the peak readings for each channel in
Display Mode (see “Display Mode” on page 23).
NOTE: The peak readings for each channel are saved until a higher peak is recorded, the
Data Logging
The GX-2009 features the ability to log data to its internal memory and download it to a
computer via the infrared communications port on the top left side. It logs gas readings during
normal operation, alarm data, calibration data, and bump test data.
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 Reading Screen.
To utilize the GX-2009’s downloading capability, you will need the GX-2009 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-
2009. 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-2009 using the USB port. The GX2009 Data Logger Management Program is available at
The USB/IrDA adapter cable is also available from RKI.
See the GX-2009 Data Logging Management Program Operator’s Manual for a complete
description of the GX-2009 Data Logging Management Program and procedures for
downloading data to a computer.
GX-2009 User Setup Program
There are some instrument operating parameters that are not accessible in either Calibration
Mode or User Setup Mode such as the calibration frequency, auto zero function, and the alarm
logic (latching or self resetting). Many of these parameters either do not typically need to be
accessed once the GX-2009 is shipped from the factory or may only need to be accessed once
because of operator preferences. These parameters can be accessed and updated if necessary
using the GX-2009 User Setup Program, a computer with the same requirements described
above in “Data Logging”, and a USB/IrDA cable if necessary. The GX-2009 User Setup
Program is available at The USB/IrDA adapter cable is
also available from RKI.
See the GX-2009 User Setup Program Operator’s Manual for a complete description of the
GX-2009 User Setup Program and procedures for accessing and updating instrument
operating parameters.
This section describes the GX-2009 in Calibration Mode. In Calibration Mode, you can move
through a menu of screens to do the following:
•Set the date and time
•Perform a fresh air adjustment (part of a calibration)
•Perform a span adjustment on all channels simultaneously (part of a calibration)
•Perform a span adjustment on one channel at a time (part of a calibration)
•Perform a bump test (if Bump Test Function is set to On using the
GX-2009 User Setup Program)
•Discharge the batteries with the REFRESH function
NOTE: You can set the GX-2009 to alert you during the startup sequence when calibration
or bump testing is due with the GX-2009 User Setup Program. See the GX-2009
User Setup Program Operator’s Manual for information on setting the Cal. Limit Display and Bump Limit Display parameters.
CAUTION: BEFORE EACH DAY’S USAGE SENSITIVITY IN THE
% LEL RANGE MUST BE TESTED ON A KNOWN CONCENTRATION OF
THE COMBUSTIBLE TARGET GAS, TYPICALLY METHANE, EQUIVALENT
TO 25 - 50% OF FULL SCALE CONCENTRATION (The %LEL full scale is
100% LEL). ACCURACY MUST BE WITHIN -0 to + 20% OF ACTUAL.
ACCURACY MAY BE CORRECTED BY FOLLOWING THE CALIBRATION
INSTRUCTIONS FOR THE COMBUSTIBLE CHANNEL BELOW.
If the combustible channel passes the above response test and does not require calibration, the
unit should still be calibrated periodically. The optimum frequency of calibration depends
heavily on how the GX-2009 is used. For example, instruments used daily may need to be
calibrated weekly or monthly, while instruments that are used only a few times a year may
need to be calibrated before each use. Typical calibration frequencies range from monthly to
quarterly. Make sure to perform the combustible channel response test as described above and
make sure to develop a calibration schedule tailored to your application that takes this test and
required calibration resulting from this test into account.
WARNING: The GX-2009 is not in operation as a gas detector while in Calibration Mode.
Although it will respond to gas in parts of AIR CAL, AUTO CAL, ONE CAL,
and BUMP TEST, there are no gas alarm indications.
1. Take the GX-2009 to a non-hazardous area and turn it off if it is on.
2. Press and hold the AIR button, then press and hold the POWER MODE button. When you
hear a beep release the buttons. The first menu item in Calibration Mode displays, the
DATE Screen.
3. Use the AIR button to move forward through Calibration Mode. When you get to the last
menu item, the START menu item, continuing will take you back to the beginning of the
menu.
4. When you arrive at the item you wish to enter, press and release the POWER MODE
button to enter that item.
5. When you need to adjust the numerical value of a parameter, increase it or decrease it, use
the AIR button to change the value. When adjusting a numerical parameter value, it is
possible to reverse the direction of adjustment. To switch from increasing to decreasing a
value or decreasing to increasing a value, do the following:
•with the parameter flashing on the screen, press and hold the AIR button
•immediately press the POWER MODE button and then release both buttons
•the direction of adjustment when you press the AIR button is now reversed
6. When you are done using the menu items in Calibration Mode, use the AIR button to
scroll through the menu items to the START item.
7. At the START screen, press and release the POWER MODE button. The GX-2009 will
begin its start-up sequence.
The Calibration Mode menu items are described below in the order in which they appear
while moving through Calibration Mode.
Entering the DATE menu item allows you to set the date and time.
1. When the DATE Screen is displayed, press and release the POWER MODE button. A
screen appears with the year flashing in the upper left, the month and day in the upper
right, and the time in the lower right.
2. Use the AIR button to display the desired year.
3. Press and release the POWER MODE button to save the setting. The month setting
flashes.
4. Repeat steps 2 and 3 to enter the month, day, hour and minute setting. When you save the
minute setting, you return to the DATE Screen.
Performing a Fresh Air Adjustment
Entering the AIR CAL menu item allows you to perform a fresh air adjustment.
Perform a fresh air adjustment in Calibration Mode when you are performing a calibration
before proceeding either to the AUTO CAL or ONE CAL menu item to perform a span
adjustment. A fresh air adjustment performed in Calibration Mode is the same as a fresh air
adjustment in Normal Mode. The AIR CAL menu item is available in Calibration Mode for
convenience when performing a complete calibration.
WARNING: Calibrate the GX-2009 in a non-hazardous environment.
1. Find a fresh air environment, an environment of normal oxygen content (20.9%) that is
free of toxic and combustible gasses.
2. When the AIR CAL screen is displayed, press and release the POWER MODE button. A
screen appears that displays the current gas readings and prompts you to press the AIR
button by displaying the “PUSH AIR” message at the bottom of the screen.
3. Press and hold the AIR button. The LCD prompts you to continue to hold the AIR button.
4. Release the AIR button when the following screen appears.
5. The unit will take a few seconds to adjust the fresh air readings, then indicate “END” to
the right of the battery icon and return to the AIR CAL Screen.
Performing a Span Adjustment in AUTO CAL
Entering the AUTO CAL menu item allows you to perform a span adjustment on all channels
simultaneously.
Perform a span adjustment as part of a calibration after performing a fresh air adjustment.
Performing a span adjustment requires the use of a calibration kit. The procedure below
describes a span adjustment of all four channels using a calibration kit that includes a 4-gas
calibration cylinder, a 0.5 LPM (liters per minute) regulator, a calibration adapter plate, and
non-absorbent sample tubing. The standard 4-gas cylinder consists of 50% LEL methane,
12% oxygen, 25 ppm H2S, 50 ppm CO, and a balance of nitrogen. If the H2S channel on your
GX-2009 is active, then use a 4-gas cylinder. If the H2S channel on your GX-2009 is not
active, you may use a 3-gas cylinder to adjust the span. The standard 3-gas cylinder consists
of 50% LEL methane, 12% oxygen, 50 ppm CO, and a balance of nitrogen. See “Parts List”
on page 67 for available calibration kits and calibration kit spare parts.
NOTE: If the combustible gas channel is calibrated to a gas other than methane, such as
isobutane, use an appropriate multigas cylinder or use single calibration to calibrate
the combustible channel.
WARNING: Calibrate the GX-2009 in a non-hazardous environment.
1. Before performing a span adjustment, perform a fresh air adjustment as described in
“Performing a Fresh Air Adjustment” on page 34.
2. At the AUTO CAL screen, press and release the POWER MODE button. A screen appears
that displays the calibration gas concentrations that the GX-2009 expects you to use.
If the displayed concentrations match the calibration cylinder concentrations, continue
with Step 3.
If any of the displayed concentrations do not match the calibration cylinder concentrations
or if you want to turn off the AUTO CAL function for a channel or channels, do the
following:
•Press and hold the AIR button, then press and momentarily hold the POWER MODE
button.
•Release both buttons as soon as you hear the buzzer sound a beep. The following
screen will display.
•You can scroll through all the channels by pressing and releasing the AIR button.
•When the desired channel is displayed, press and release the POWER MODE button
to select the channel for a calibration gas value update. In the example below, the
combustible channel has been selected and the current calibration gas value is 50
%LEL.
•Use the AIR button to adjust the calibration gas value to the desired value.
•If you want to turn the AUTO CAL function for the selected channel off so that a span
adjustment will not be performed on this channel, set the calibration gas value to OFF
by adjusting the reading down from the lowest value or up from the highest value.
•Press and release the POWER MODE button to accept the displayed value. The
previous screen will return.
•Repeat the steps above for any other channels that require calibration gas value
updates.
•When you are done updating calibration gas values, use the AIR button to scroll to the
following screen.
•Press and release the POWER MODE button to return to the screen that displays the
3. Use the sample tubing to connect the calibration adapter plate to the regulator. Attach the
tubing to the adapter plate on the inlet side as shown below in Figure 9.
Figure 9: Calibration Kit Assembly
4. Push the adapter plate onto the GX-2009’s sensor face. Make sure the adapter plate is
oriented as shown in Figure 10 below with the sensor names on the adapter plate matching
up with the sensor names on the instrument.
5. Press and release the POWER MODE button. The LCD will display the current gas
0 20.9
AUTO CAL
CO ppm H2S ppm
CH4 %LEL OXY vol%
0 0.0
PASS
FAIL
CH4 %LEL
AUTO CAL
readings and “AUTO CAL” will flash.
6. For toxic gas cylinders (like cylinders containing H
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.
7. Allow the gas to flow for two minutes.
8. Press and release the POWER button.
9. The GX-2009 will attempt to make a span adjustment on all channels.
10. If the span adjustment is successful, the LCD will show the following screen before
returning to the AUTO CAL screen.
11. If the span adjustment fails, the LCD will show the following screen indicating which
channel or channels failed, the alarm LEDs will flash, and the buzzer will sound a double
pulsing tone.
S), it is important to vent the regulator
2
In this example, the CH4 channel failed the span adjustment. Press and release the
POWER MODE button to clear the failure indication and return to the AUTO CAL
screen.
See “Troubleshooting” on page 56 to investigate the cause of the failure and replace the
failed sensor or sensors if necessary.
12. Turn the regulator on/off knob clockwise to close it.
13. Remove the calibration adapter plate from the instrument.
14. Remove the regulator from the calibration gas cylinder.
15. Leave the regulator connected to the calibration adapter plate for convenience.
16. Store the components of the calibration kit in a safe and convenient place.
Performing a Span Adjustment in ONE CAL
Entering the ONE CAL menu item allows you to perform a span adjustment on one channel at
a time. This feature is useful for situations when you do not need to calibrate all channels,
such as when you are replacing a sensor.
Perform a span adjustment as part of a calibration after performing a fresh air adjustment.
Performing a span adjustment requires the use of a calibration kit. The procedure below
describes a span adjustment of one channel using a calibration kit that includes a 4-gas
calibration cylinder, a 0.5 LPM (liters per minute) regulator, a calibration adapter plate, and
non-absorbent sample tubing. The standard 4-gas cylinder consists of 50% LEL methane,
12% oxygen, 25 ppm H2S, 50 ppm CO, and a balance of nitrogen. If the H2S channel on your
GX-2009 is active, then use a 4-gas cylinder so that you can calibrate all channels when
necessary. If the H2S channel on your GX-2009 is not active, you may use a 3-gas cylinder.
The standard 3-gas cylinder consists of 50% LEL methane, 12% oxygen, 50 ppm CO, and a
balance of nitrogen. In the example below, the CH4 channel’s span is adjusted. See “Parts
List” on page 67 for available calibration kits and calibration kit spare parts.
Calibration cylinders that contain only one target gas may also be used for single calibration.
For channels other than oxygen, RKI Instruments, Inc. recommends that you use a cylinder
that contains a concentration of 10-50% of the full scale value of the target gas. For example,
if you are calibrating the combustible gas channel, your calibration cylinder should have a
combustible gas concentration between 10% LEL and 50% LEL. For the oxygen channel,
RKI Instruments, Inc. recommends using 100% nitrogen to perform the adjustment but any
concentration between 0% oxygen (100% nitrogen) and 17% oxygen can be used to make the
adjustment.
NOTE: If your combustible gas channel is calibrated to a gas other than methane, such as
isobutane, use an appropriate gas cylinder to perform the calibration.
WARNING: Calibrate the GX-2009 in a non-hazardous environment.
1. Before performing a span adjustment, perform a fresh air adjustment as described in
“Performing a Fresh Air Adjustment” on page 34.
2. At the ONE CAL screen, press and release the POWER MODE button. A channel
selection screen appears that displays the CH
channel.
4
If the CH4 channel is the one you want to span adjust, skip to Step 4.
If you want to span adjust a different channel, continue with Step 3.
3. Scroll through the channels using the AIR button until the channel you want to span adjust
is displayed. The gas channels are displayed in the following order along with an escape
option: CH4, oxygen, H2S, CO, ESCAPE.
If you want to abort the span adjustment, scroll through the channels until you arrive at the
screen that indicates “ESCAPE” to the right of the battery icon, then press and release the
POWER MODE button to return to the ONE CAL screen.
4. Use the sample tubing to connect the calibration adapter plate to the regulator. Attach the
tubing to the adapter plate on the inlet side as shown below in Figure 11.
5. Push the adapter plate onto the GX-2009’s sensor face. Make sure the adapter plate is
Flow
%LEL
H
2
S
O
2
To Fixed Flow
Regulator
CO
AIR
POWER
MODE
RKI GX-2009
H
2
S CO %LEL O
2
Adapter Plate
0
ONE CAL
CH4 %LEL
oriented as shown in Figure 12 below with the sensor names on the adapter plate matching
up with the sensor names on the instrument.
6. Press and release the POWER MODE button, the current gas reading for the selected
channel is displayed.
7. For toxic gas cylinders (like cylinders containing H
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.
8. Allow the gas to flow for two minutes.
9. Adjust the display gas reading using the AIR button to match the calibration cylinder’s
target gas concentration. See Step 5 on page 33 for instructions to adjust a parameter using
the AIR button.
11. The GX-2009 will make the span adjustment and will return to the channel selection
- - -
ONE CAL
CH4 %LEL
ESCAPE
ONE CAL
screen.
The channel that was just span adjusted will be displayed.
12. If you want to span adjust additional channels, repeat Step 3 through Step 11 for each
channel while gas is still flowing. Make the reading adjustment right away since gas has
been flowing for more than two minutes. If you need to calibrate more than two channels,
use the AUTO CAL menu item to calibrate the GX-2009.
13. Turn the regulator on/off knob clockwise to close it.
14. When you are finished with span adjustments, scroll to the screen that indicates
“ESCAPE.”
15. Press and release the POWER MODE button to return to the ONE CAL Screen.
16. Remove the calibration adapter plate from the instrument.
17. Remove the regulator from the calibration gas cylinder.
18. Leave the regulator connected to the calibration adapter plate for convenience.
19. Store the components of the calibration kit in a safe and convenient place.
NOTE: Bump Test Function must be set to On using the GX-2009 User Setup Program in
order for BUMP to appear in Calibration Mode. If Bump Test Function is set to
Off, BUMP will not appear. See the GX-2009 User Setup Program Operator’s
Manual for instructions. The factory setting for Bump Test Function is Off.
Entering the BUMP menu item allows you to perform a bump test on all channels
simultaneously to determine if the instrument is responding properly to gas.
Performing a bump test requires the use of a calibration kit. The procedure below describes a
bump test of all four channels using a calibration kit that includes a 4-gas calibration cylinder,
a 0.5 LPM (liters per minute) regulator, a calibration adapter plate, and non-absorbent sample
tubing. The standard 4-gas cylinder consists of 50% LEL methane, 12% oxygen, 25 ppm H2S,
50 ppm CO, and a balance of nitrogen. If the H2S channel on your GX-2009 is active, then use
a 4-gas cylinder. If the H2S channel on your GX-2009 is not active, you may use a 3-gas
cylinder to perform the bump test. The standard 3-gas cylinder consists of 50% LEL methane,
12% oxygen, 50 ppm CO, and a balance of nitrogen. See “Parts List” on page 67 for available
calibration kits and calibration kit spare parts.
NOTE: If your combustible gas channel is calibrated to a gas other than methane, such as
isobutane, use an appropriate gas cylinder to perform the calibration.
WARNING: Bump test the GX-2009 in a non-hazardous environment.
1. Before performing a bump test, perform a fresh air adjustment as described in
“Performing a Fresh Air Adjustment” on page 34.
2. At the BUMP screen, press and release the POWER MODE button. A screen appears that
displays the gas concentrations that the GX-2009 expects you to use.
NOTE: The bump test gas concentrations are the same as the AUTO CAL gas
concentrations.
If the values are not correct, you can change them by changing the AUTO CAL gas values
in Calibration Mode or User Setup Mode or by using the Data Logger Management
Program or the User Setup Program. To exit this screen and return to the main menu, press
and release the AIR button.
3. Use the sample tubing to connect the calibration adapter plate to the regulator. Attach the
tubing to the adapter plate on the inlet side as shown below in Figure 13.
4. Push the adapter plate onto the GX-2009’s sensor face. Make sure the adapter plate is
oriented as shown in Figure 14 below with the sensor names on the adapter plate matching
up with the sensor names on the instrument.
5. Press and release the POWER MODE button. The LCD will display the current gas
0 20.9
BUMP 30
CO ppm H2S ppm
CH4 %LEL OXY vol%
0 0.0
P F
BUMP
CO ppm H2S ppm
CH4 %LEL OXY vol%
F F
45 18.9
BUMP
CO ppm H2S ppm
CH4 %LEL OXY vol%
10 1.0
BUMP
readings and the instrument will count down from 30.
6. For toxic gas cylinders (like cylinders containing H
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.
If you wish to cancel the bump test or a calibration initiated because of a failed bump test,
press and hold the AIR button until you return to the BUMP screen.
7. When the bump test countdown reaches 0, the unit will determine the bump test results
and proceed as described in either Step 8 or Step 9 depending on the setting of
Calibration After Bump Test Failed. See the User Setup Program Operator’s Manual for
a complete description of this parameter.
8. When Calibration After Bump Test Failed is set to OFF:
•The instrument will display which channels passed or failed the bump test.
•To view the bump test gas readings press the AIR button.
S), it is important to vent the regulator
2
•To return to the BUMP screen in Calibration Mode, press POWER MODE. You may
also press POWER MODE to return to the BUMP screen without first viewing the
bump test gas readings.
See “Troubleshooting” on page 56 to investigate the cause of the failure and
replace the failed sensor or sensors if necessary.
•Turn the regulator on/off knob clockwise to close it.
•To view the calibration gas reading, press the AIR button again.
52 20.9
/CAL
CO ppm H2S ppm
CH4 %LEL OXY vol%
48 0.0
BUMP
REFRESH
•To return to the BUMP screen in Calibration Mode, press POWER MODE at any
time.
•Turn the regulator on/off knob clockwise to close it.
10. Remove the calibration adapter plate from the instrument.
11. Remove the regulator from the calibration gas cylinder.
12. Leave the regulator connected to the calibration adapter plate for convenience.
13. Store the components of the calibration kit in a safe and convenient place.
Discharging the Batteries with the REFRESH Function
Entering the REFRESH menu item allows you to discharge the batteries.
If the GX-2009’s batteries are repeatedly only partially discharged before being charged or
only partially charged before being discharged, the instrument’s runtime may be reduced. The
NiMH batteries used in the GX-2009 are resistant to this effect, but if you notice that the
runtime is decreasing, run the REFRESH function two or three times and see if the runtime
recovers. If the batteries are fully charged, the REFRESH function will take about three hours
to discharge the batteries. If the instrument’s runtime does not recover, the batteries may need
to be replaced.
1. When the REFRESH screen is displayed, press and release the POWER MODE button.
Two screens begin alternating prompting you to answer whether or not you want to run the
REFRESH function.
2. To run the REFRESH function, press and release the POWER MODE button. The
following screen will be displayed and the fill inside the battery icon will begin to flash.
The GX-2009 is now discharging the batteries.
If you do not want to run the REFRESH function, press and release the AIR button. The
unit will return to the REFRESH screen.
3. If you want to abort the battery discharge at any time, press and release the AIR button and
the unit will return to the REFRESH screen.
4. When the unit is done discharging the batteries, the buzzer will sound a double pulsing
tone, the battery icon will flash, and the following screen will appear.
5. Press and hold the POWER MODE button until the unit turns off, then release it. Recharge
the GX-2009’s batteries. See “Recharging the GX-2009’s NiMH Batteries” on page 57.
This section describes the GX-2009 in User Setup Mode. User setup mode has the same menu
items as Calibration Mode with the addition of the ALARM--P menu item which allows you
to set the alarm points and the PASSWORD menu item which allows you to turn the password
feature on or off and set the password. The common menu items are included in User Setup
Mode as a convenience to avoid turning off the unit and entering Calibration Mode if you are
updating alarm points and also want to use one of the other menu items. In User Setup Mode,
you can move through a menu of screens to do the following:
•Set the date and time (same as in Calibration Mode)
•Perform a fresh air adjustment (same as in Calibration Mode)
•Perform a span adjustment on all channels simultaneously (same as in Calibration Mode)
•Perform a span adjustment on one channel at a time (same as in Calibration Mode)
•Set the alarm points
•Discharge the batteries with the REFRESH function (same as in Calibration Mode)
•Turn the password feature on or off and define the password
NOTE: You can set the GX-2009 to alert you during the startup sequence when calibration
or bump testing is due with the GX-2009 Setup Program. See the GX-2009 Setup
Program Operator’s Manual for information on setting the Cal. Limit Display and
Bump Limit Display parameter.
The description of the menu items that are common to Calibration Mode and User Setup
Mode will refer you to the appropriate pages in the Calibration Mode section.
Using User Setup Mode
WARNING: The GX-2009 is not in operation as a gas detector while in User Setup Mode.
Although it will respond to gas in parts of AIR CAL, AUTO CAL, ONE CAL,
and BUMP TEST, there are no gas alarm indications.
1. Take the GX-2009 to a non-hazardous area and turn it off if it is on.
2. Press and hold the AIR button, then press and hold the POWER MODE button. You will
hear a beep after one second. Continue to hold both the AIR and the POWER MODE
button.
3. After three seconds you will hear a second beep. Release both buttons when you hear the
second beep.
4. If the PASSWORD menu item is set to on, the following screen will appear with the first
digit flashing prompting you to enter the password.
•Use the AIR button to scroll through the numbers 0-9 until you arrive at the desired
value, then press and release the POWER MODE button to accept the value.
•Repeat the above procedure for each digit.
•When you have set and accepted the last digit of the password, the first menu item in
User Setup Mode will appear, the DATE Screen.
•If you entered the incorrect password, an error screen will appear.You must use the
POWER MODE button to turn the unit off and try again if you wish to enter User
Setup Mode or turn on the unit and proceed to Measuring Mode.
5. If the PASSWORD menu item is set to oFF, the first menu item in User Setup Mode
displays, the DATE Screen.
6. Use the AIR button to move forward through User Setup Mode. When you get to the last
menu item, the START menu item, continuing will take you to the beginning of the menu.
7. When you arrive at the item you wish to enter, press and release the POWER MODE
button to enter that item.
8. When you need to adjust the numerical value of a parameter, increase it or decrease it, use
the AIR button to change the value. When adjusting a numerical parameter value, it is
possible to reverse the direction of adjustment. To switch from increasing to decreasing a
value or decreasing to increasing a value, do the following:
•with the parameter flashing on the screen, press and hold the AIR button
•immediately press the POWER MODE button and then release both buttons
•the direction of adjustment when you press the AIR button is now reversed
Entering the ALARM--P menu item allows you to set the alarm points for each channel.
Table 5 below lists the factory set alarm points for each channel.
Table 5: Factory Set Alarm Points
ChannelWarningAlarmSTELTWA
O
2
Combustibles 10% LEL50% LELn/an/a
CO25 ppm50 ppm200 ppm 25 ppm
H
S5 ppm30 ppm5 ppm1 ppm
2
19.5%
Decreasing
23.5%n/an/a
All of the alarms are increasing alarms, the alarm condition actuates when the gas level
increases above the alarm point, except for the O2 Warning alarm. The O2 Warning alarm is a
decreasing alarm. The O2 Warning condition actuates when the oxygen level decreases below
the alarm point.
For the combustibles channel, it is not possible to adjust either the Warning or Alarm settings
to be higher than 60 %LEL. In addition, the Warning setting cannot be adjusted higher than
the Alarm setting for all channels.
1. At the ALARM--P screen, press and release the POWER MODE button. The following
screen will display showing the combustible channel.
2. You can scroll through all the channels by pressing and releasing the AIR button.
3. When the desired channel is displayed, press and release the POWER MODE button to
select the channel for an alarm point adjustment. In the example below, the combustible
channel has been selected and the Warning alarm point is displayed flashing.
4. Use the AIR button to adjust the Warning setpoint to the desired value.
5. Press and release the POWER MODE button to save the new Warning setpoint. A screen
with the Alarm setpoint flashing is displayed.
6. Use the AIR button to adjust the Alarm setpoint to the desired value.
7. Press and release the POWER MODE button to save the new Alarm setpoint. The display
will return to the following screen.
NOTE: If you are setting the H2S or CO channel’s alarm points, you will also see screens for
setting the TWA and STEL alarms.
8. Repeat Step 2 through Step 7 for any other channels whose alarm points you want to
change.
9. When you are done, scroll to the following screen.
10. Press and release the POWER MODE button to return to the
ALARM--P screen.
Setting the Password
You can password protect entry into the User Setup Mode with the password feature. Entering
the PASSWORD menu item allows you to turn this feature on or off and enter a password if
you turn it on.
The factory setting for the password feature is oFF.
1. At the PASSWORD screen, press and release the POWER MODE button. A screen will
appear that shows the current password feature setting.
2. Press and release the air button to change the displayed setting. When the desired setting is
displayed, press and release the POWER MODE button to save the setting.
3. If the password feature was set to oFF, the unit will exit the PASSWORD menu item and
return to the PASSWORD screen.
With the password feature set to oFF, you will be able to enter User Setup Mode without
entering a password.
4. If the password feature was set to on, the following screen will appear with the first digit
flashing prompting you to enter the password you want to use.
5. Use the AIR button to scroll through the numbers 0 - 9.
6. When the desired number is displayed for the first digit, press and release the POWER
MODE button to save the number.
7. The next digit will begin flashing.
8. Repeat Step 5 through Step 7 until you have set all four of the digits.
9. When you save the last digit, the unit will return to the PASSWORD screen.
This section describes troubleshooting procedures for the GX-2009. It also describes how to
recharge the GX-2009’s batteries, check the combustible sensor’s condition, replace the unit’s
filters, sensor cover, and gas sensors.
WARNING: RKI Instruments, Inc. recommends that service, calibration, and repair of
Troubleshooting
The troubleshooting table describes error messages, symptoms, probable causes, and
recommended action for problems you may encounter with the GX-2009.
RKI equipment be performed by personnel properly trained for this work.
Replacing sensors and other parts with original equipment does not affect th e
intrinsic safety of the instrument.
Table 6: Troubleshooting the GX-2009
SymptomsProbable CausesRecommended Action
•The LCD is blank.•The unit may have been turned
off.
•The batteries may need
recharging.
•The unit shows
abnormally high or
low readings but
other gas detection
instruments do not.
•“FAIL” displays
during span
adjustment in AUTO
CAL or unable to set
the response readings
during span
adjustment in ONE
CAL.
•The GX-2009 may need to be
calibrated.
•The sensor for the affected
channel(s) may need
replacement.
•The AUTO CAL calibration gas
values may not match the
cylinder gas concentrations.
(AUTO CAL only)
•The H
•The sample gas is not reaching
•The calibration cylinder may be
•The sensor for the affected
S removal filter disk
2
over the combustible sensor or
the charcoal filter disk over the
CO sensor are saturated.
the sensor because of a bad
connection
out of gas or is outdated.
channel(s) may need
replacement.
1. To turn on the unit, press and hold
the POWER MODE button until
you hear a beep.
2. If the unit does not turn on, the
batteries may need to be recharged.
Recharge the batteries with the
charging station.
3. If the difficulties continue, contact
RKI Instruments, Inc. for further
instruction.
1. Calibrate the unit.
2. Replace the sensor for the affected
channel(s).
3. If the difficulties continue, contact
RKI Instruments for further
instruction.
1. Confirm that the AUTO CAL
calibration gas values match the
calibration gas cylinder.
2. Change H
or the charcoal filter disk.
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.
Figure 15: Connecting the Charging Station’s AC Adapter
Recharging the GX-2009’s NiMH Batteries
WARNING: To prevent ignition of a hazardous atmosphere, batteries must only be
changed or charged in an area known to be nonhazardous.
CAUTION: Use with RKI NiMH battery set 49-1609RK. Charge only with RKI AC charger
p/n 49-2170RK-0X (where X = 1, 2, 3, 4, or 5) or RKI DC charger 49-2171RK.
Use of other rechargeable batteries or chargers or charging of other
rechargeable batteries in the GX-2009 will void the warranty.
1. Verify that the GX-2009 is off.
2. Confirm that the adapter’s DC output cord is plugged into the charger. If a multiinstrument charging station is being used, the same AC adapter is used as for the single
instrument charging station.
3. If using an AC powered charging station, plug the AC adapter into an electrical outlet.
4. Put the GX-2009 in the charging base. Tabs at the top and bottom of the charging base
POWER
MODE
AIR
Retaining Tabs
RKIGX-2009
H
2
SCO%LELO
2
Figure 17: Putting the GX-2009 in the Charging Base
retain the instrument.
5. While the unit is being charged, the red charging LED on the top face of the charger is on.
6. When the charging LED turns off, the GX-2009’s batteries are fully charged. It takes
approximately 3 hours to recharge a fully discharged battery set.
7. To verify whether the batteries are fully recharged, remove the unit from
the charging base, then press the POWER MODE button to start up the
unit. If the battery icon on the LCD is fully colored in, then the unit has
been completely recharged.
NOTE: A battery set will have a typical service life of 500 charging cycles.
When using the GX-2009, draining the batteries as much as possible before recharging them
will help maintain the maximum operating time. If the batteries are regularly only partially
drained before charging or partially charged before using the instrument, the battery may
experience a “memory effect” and the run time of the instrument may be decreased. If you
notice this effect with your instrument, use the REFRESH function described in “Discharging
the Batteries with the REFRESH Function” on page 48 to discharge your batteries before
recharging them.
WARNING: Replace the batteries in a non-hazardous environment.
Replace the battery set when it no longer holds a charge.
1. Verify that the GX-2009 is off.
2. Use a small phillips head screwdriver to remove the four screws that hold the two halves
of the case together. They are accessible from the back of the instrument.
3. Grasp the instrument by the front case with your left hand.
4. Grasp the rear case near the top where it is deepest with your right hand and gently pull the
top of the rear case slightly away from the top of the front case, rotating it about the
5. As you pull the top of the rear case away from the front case, you will feel a slight click as
the bottom of the rear case separates from the bottom of the front case. Pull the rear case
away from the front case. Keep the instrument flat and steady so that the batteries do not
drop out of the case.
6. The batteries will be visible in the front case on the main circuit board. Once the front case
is removed, they are no longer held in place and can be easily removed.
7. Remove each battery by gently pulling it away from the circuit board. Each battery has an
integral holder that provides electrical connection to the circuit board.
8. Replace each battery with a new one. Note the polarity markings on the circuit board and
batteries when installing each battery. Tabs on the bottom of each battery match up with
holes in the circuit board.
9. Reinstall the rear case to the front case with the four case screws.
Checking the Combustible Gas Sensor’s Condition
If you suspect that the combustible sensor has been contaminated or may be reaching the end
of its operational life, do the following to confirm it is still operating properly:
1. Perform a fresh air adjustment as described in “Performing a Fresh Air Adjustment” on
page 34.
2. Apply calibration gas as described in “Performing a Span Adjustment in ONE CAL” on
page 40.
3. Instead of setting the gas reading to match the calibration gas concentration, adjust the gas
reading as high as possible.
4. A new sensor can typically be adjust to more than twice the calibration gas concentration.
If you are not able to adjust the combustible gas reading to be at least 10% higher than the
calibration gas concentration, then the sensor should be replaced as soon as possible.
Figure 23: Removing the Sensor Retainer and Replacing the Scrubber Filters
Replacing the Scrubber Filters
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 can absorb H2S for 33 ppm hours and
should be replaced after that much exposure. With this many ppm hours of absorption, the
H2S filter disk should be replaced after 80 minutes of exposure to 25 ppm H2S. This equates
to replacing the H2S filter disk after 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.
WARNING: Replace the scrubber filters in a non-hazardous environment.
1. Verify that the GX-2009 is off.
2. Unscrew the two screws that secure the sensor retainer and sensor cover retainer to the
GX-2009 and remove them.
3. Using a small flat blade screwdriver, gently pry each side of the sensor cover retainer
away from the sensor retainer.
4. Remove the sensor cover and sensor retainer gasket to gain access to the scrubbers.
5. The charcoal filter disk is located in the CO sensor diffusion port. One filter disk is used.
One H2S removal filter disk is located in the combustible gas diffusion port.
CAUTION: When replacing a sensor, verify that the sensor is properly aligned with its
socket before inserting it into the socket. The CO and H2S sensors have
alignment slots which match up with alignment tabs in the sockets. The
combustible gas sensor has two non-polarized contacts which must line up with
the contacts in the socket. Forcing a sensor into its socket may damage the
sensor or the socket.
6. Snap the sensor retainer back onto the case, then secure it to the GX-2009 with the two
screws. The sensor retainer’s tabs that snap onto the case are keyed so you can only snap it
to the case one way.
7. Calibrate the new sensor as described in “Performing a Span Adjustment in AUTO CAL”
on page 35 or “Performing a Span Adjustment in ONE CAL” on page 40.