RKI Instruments 65-2434RK User manual

65-2434RK
Carbon Monoxide Transmitter
Operator’s Manual
Part Number: 71-0061RK
Revision: D
Released: 2/16/11
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65-2434RK CO Transmitter
WARNING
Read and understand this instruction manual before operating
detector. Improper use of the detector could result in bodily harm
or death.
Periodic calibration and maintenance of the detector is essential
for proper operation and correct readings. Please calibrate and
maintain this detector regularly! Frequency of calibration
depends upon the type of use you have and the sensor types.
Typical calibration frequencies for most applications are between
3 and 6 months, but can be required more often or less often
based on your usage.
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65-2434RK CO Transmitter
Product Warranty
RKI Instruments, Inc. warranties gas alarm equipment sold by us to be free from defects in
materials, workmanship, and performance for a period of one year from date of shipment
from RKI Instruments, Inc. Any parts found defective within that 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 operator’s 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.
THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY AND ALL OTHER
WARRANTIES AND REPRESENTATIONS, EXPRESSED OR IMPLIED,
AND ALL OTHER OBLIGATIONS OR LIABILITIES ON THE PART OF
RKI INSTRUMENTS, INC. INCLUDING BUT NOT LIMITED TO, THE
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE. IN NO EVENT SHALL RKI INSTRUMENTS,
INC. BE LIABLE FOR INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
LOSS OR DAMAGE OF ANY KIND CONNECTED WITH THE USE OF
ITS PRODUCTS OR FAILURE OF ITS PRODUCTS TO FUNCTION OR
OPERATE PROPERLY.
This warranty covers instruments and parts sold to users 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 the replacement of parts or our complete
goods.
a) Absorbent cartridges d) Batteries
b) Pump diaphragms and valves e) Filter elements
c) Fuses
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65-2434RK CO Transmitter
Table of Contents
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
CO Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Charcoal Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Amplifier PCB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Enclosure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Mounting the CO Transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Wiring the CO Transmitter to a Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Setting the Zero Signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Replacing Components of the CO Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Calibration Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Returning to Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
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65-2434RK CO Transmitter • 1
Overview
This manual describes the 65-2434RK carbon monoxide (CO) transmitter. This manual
also describes how to install, start up, maintain, and calibrate the transmitter. A parts list
at the end of this manual lists replacement parts and accessories for the CO transmitter.
Specifications
Table 1 lists specifications for the CO transmitter.
WARNING: When using the 65-2434RK, you must follow the instructions and warnings
in this manual to assure proper and safe operation of the 65-2434RK and to
minimize the risk of personal injury. Be sure to maintain and periodically
calibrate the 65-2434RK as described in this manual.
Table 1: Specifications
Target Gas Carbon monoxide (CO)
Sampling Method Diffusion
Input Voltage 10 VDC - 30 VDC
Signal Output 4 - 20 mA
Detection Range 0 to 300 PPM (parts per million)
Accuracy ± 5% of reading or ± 5 ppm CO (whichever is greater)
Response Time 90% in 30 seconds
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2 • 65-2434RK CO Transmitter
Description
This section describes the components of the CO transmitter. The transmitter consists of
the CO sensor, charcoal filter, amplifier printed circuit board (PCB), and enclosure.
Figure 1: CO Transmitter Component Location
CO Sensor
The sensor is cylindrical with the sensing face on the top and the connection pins on the
bottom. The sensor plugs into the amplifier PCB with the four pins. The sensor is exposed
to the ambient air through an opening in the enclosure cover. Through a series of chemical
and electrical reactions, the sensor produces an electrical output that is proportional to the
detection range of the transmitter.
Charcoal Filter
The disc-shaped charcoal filter is secured to the sensing face of the sensor by a rubber
boot. The filter prevents interference gases (hydrogen sulfide [H2S] and certain
hydrocarbons) from producing false CO readings.
Amplifier PCB
The amplifier PCB converts the electrical output from the sensor to a 4 to 20 mA signal
(that is proportional to the detection range) and transmits the signal to a gas monitoring
controller. The amplifier PCB includes the interconnect terminal strip, sensor sockets, span
pot, zero pot, and test points (see Figure 1).
Amplifier PCB
Zero Pot
Span Pot
Test Point CAL-
Factory Set Pot
Amplifier PCB Mounting
Screw (under sensor)
Cable Bushing
Amplifier PCB
Mounting Screw
Sensor (w/charcoal
filter & boot)
R
CAL-
TB1 CAL+
+V
FB
B
SPAN
Enclosure
(shown w/out cover)
Interconnect
Terminal Strip
Test Point
CAL+
ZERO
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65-2434RK CO Transmitter • 3
Interconnect Terminal Strip
The interconnect terminal strip is the four-point terminal strip on the lower left side of the
amplifier PCB. Use the interconnect terminal strip to connect the transmitter to a
controller.
Sensor Sockets
There are four sensor sockets located in a circular pattern near the top of the amplifier
PCB. The sensor plugs into these sockets.
Span Pot
The span pot is near the bottom right corner of the amplifier PCB. Use the span pot to
adjust the transmitter’s response output during the calibration procedure.
Zero Pot
The zero pot is above the span pot. Use the zero pot to adjust the transmitter’s target gas-
free output during the start-up and calibration procedures.
CAUTION: There is a third potentiometer on the PCB, the null potentiometer. It is factory-set.
Do not adjust it.
Test Points
The test points (labeled CAL+ and CAL-) are on the right of the interconnect terminal
strip. The test points produce a 100 - 500 mV output that is proportional to the
transmitter’s 4 - 20 mA output. Use the test points and a voltmeter to measure the
transmitter’s output during the start-up and calibration procedures.
Enclosure
The enclosure enables you to install the CO transmitter at a mounting site that is remote
from the controller. The enclosure also protects the amplifier PCB and wiring connections
made to the transmitter. Use the cable bushing on the bottom of the enclosure to connect
wiring from the amplifier PCB to a controller.
Use the enclosure’s two mounting holes, accessible with the cover removed, to mount the
CO transmitter to a vertical surface at the monitoring site. Use the cover on the front of the
enclosure to access the interior of the enclosure.
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4 • 65-2434RK CO Transmitter
Installation
This section describes procedures to mount the CO transmitter in the monitoring
environment and wire the transmitter to a gas monitoring controller.
Mounting the CO Transmitter
1. Select a mounting site that is representative of the monitoring environment. Consider
the following when you select the mounting site.
• Select a site where the transmitter is not likely to be bumped or disturbed. Make
sure there is sufficient room to perform start-up, maintenance, and calibration
procedures.
• Select a site where the target gas is likely to be found first.
NOTE: If your application does not require a specific mounting site, mount the
transmitter at approximately breathing level.
Figure 2: Mounting the CO Transmitter
2. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
3. At the monitoring site, use #6 screws through the enclosure’s two mounting holes to
secure it to a vertical surface.
4. Secure the cover to the enclosure with the four cover screws.
2.52
CO Sensor
.24
.54
1.50 1.42
3.39
3.86
Ø.160 mounting hole,
2X, Accessible With Lid
Removed
.80 max Cable Bushing
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65-2434RK CO Transmitter • 5
Wiring the CO Transmitter to a Controller
WARNING: Always verify that the power source is off before you make wiring
connections.
1. Turn off the controller.
2. Turn off or unplug incoming power at the power source end.
3. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
4. Guide a two-conductor, shielded cable through the cable bushing at the bottom of the
enclosure.
5. Connect the two wires to the interconnect terminal strip as follows (see Figure 3.)
• Connect the positive wire to the terminal labeled +V.
• Connect the feedback wire to the terminal labeled FB.
CAUTION: Leave the shield drain wire insulated and disconnected at the transmitter. You will
connect the opposite end of the cable’s drain wire at the controller.
6. Secure the cover to the enclosure.
7. Route the cable leading from the CO transmitter through one of the conduit hubs at
the controller housing.
CAUTION: Do not route controller power and transmitter wiring through the same conduit hub.
The power cable may disrupt the transmission of the transmitter signal to the
controller.
8. Connect the wires to the applicable controller transmitter terminal strip as shown in
Figure 3 below.
Figure 3: Wiring the CO Transmitter to a Controller
+ (10 VDC - 30 VDC)
4-20mAIn(FB)
Controller or Recording
Device
CAL-
TB1 CAL+
SPAN
ZERO
B
FB
R
+V
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6 • 65-2434RK CO Transmitter
9. Connect the cable’s drain to an available chassis ground at the controller. RKI
controllers typically have a ground stud that can be used to ground the cable’s drain
wire.
Start Up
This section describes procedures to start up the CO transmitter and place the transmitter
into normal operation.
Introducing Incoming Power
1. Complete the installation procedures described earlier in this manual.
2. Verify that the power wiring to the controller is correct and secure. Refer to the
controller instruction manual.
3. Turn on or plug in the incoming power at the power source end, then turn on the
controller.
4. Verify that the controller is on and operating properly. Refer to the controller
operator’s manual.
CAUTION: Allow the transmitter to warm up for 5 minutes before you continue with the next
section, “Setting the Zero Signal”.
Setting the Zero Signal
NOTE: If you can verify that the detector is in a fresh air environment (environment
known to be of normal oxygen content and free of toxic and combustible gases),
it is not necessary to apply zero air when verifying or setting the fresh air
reading.
The procedure below describes applying zero emission air, usually called zero air, using a
calibration kit that includes a calibration cup, calibration gas, sample tubing, and a fixed
flow regulator with an on/off knob. RKI Instruments, Inc. recommends using a 0.5 LPM
(liters per minute) fixed flow regulator.
1. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
2. Set a voltmeter to measure in the millivolt (mV) range.
3. Plug the voltmeter leads into the test points on the amplifier PCB. Plug the positive
lead into the test point labeled CAL+; plug the negative lead into the test point labeled
CAL-.
4. Screw the regulator into the zero air calibration cylinder.
5. Use the sample tubing to connect the regulator to the calibration cup.
6. Turn the regulator’s on/off knob counterclockwise to open it.
7. Hold the calibration cup against the CO sensor’s face. Leave the rubber boot and
sealing spacer on the sensor when calibrating. Hold the cup on gently to allow gas to
escape and avoid pressurizing the sensor’s sensing face.
8. Allow the gas to flow for 2 minutes.
9. Verify a voltmeter reading of 100 mV (±2 mV).
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65-2434RK CO Transmitter • 7
10. If necessary, use a flat-blade screwdriver to adjust the zero pot until the voltmeter
reading is 100 mV (±2 mV).
11. Turn the regulator on/off knob clockwise to close it.
12. Remove the calibration cup from the sensor face.
13. Unscrew the regulator from the zero air calibration cylinder. For convenience, leave
the sample tubing connected to the regulator and the calibration cup.
14. Store the components of the calibration kit in a safe and convenient place.
15. Remove the voltmeter leads from the test points.
16. Secure the cover to the enclosure.
Maintenance
This section describes maintenance procedures. It includes preventive maintenance,
troubleshooting, and component replacement procedures.
Preventive Maintenance
This section describes a preventive maintenance schedule to ensure the optimum
performance of the CO transmitter. It includes daily, monthly, and quarterly procedures.
Daily
Verify a display reading of 0 PPM CO at the controller. Investigate significant changes in
the display reading.
Monthly
This procedure describes a test to verify that the CO transmitter responds properly to
carbon monoxide.
NOTE: Performing a response test on the CO transmitter may cause alarms. Be sure to
put the controller into its calibration program or disable external alarms before
performing this test.
Preparing for the response test
1. Place the controller into its calibration program or disable external alarms.
2. Verify that the controller display reading for the channel you are testing is 0.
If the display reading is not zero, set the zero reading of the transmitter as described
in the Start Up section of this manual, then continue this procedure.
3. Assemble the calibration kit as described in the Calibration section of this manual.
4. Set a voltmeter to measure in the millivolt (mV) range.
5. Remove the enclosure cover, then plug the voltmeter leads into the test points on the
amplifier PCB.
Plug the positive lead into the test point labeled CAL+; plug the negative lead into the
test point labeled CAL-.
6. Use the following formula to determine the correct test points output for the test
sample.
Output (mV) = (calibrating sample/fullscale) X 400 + 100
For example, with a test sample of 50 PPM CO and a fullscale setting of
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8 • 65-2434RK CO Transmitter
300 PPM, the correct output is 167 mV.
167 (mV) = (50/300) X 400 +100
Performing the response test
1. Turn the regulator’s on/off knob counterclockwise to open it. Gas will begin to flow.
2. Hold the calibration cup against the CO sensor’s face. Leave the rubber boot and
charcoal filter on the sensor when calibrating. Hold the cup on gently to allow gas to
escape and avoid pressurizing the sensor’s sensing face.
3. When the reading on the voltmeter stabilizes, after approximately two minutes, verify
that the reading is within ± 20% of the response reading you determined earlier.
NOTE: If the readings are not within ± 20% of the correct response reading, calibrate the
transmitter as described in the Calibration section of this manual.
4. Turn the regulator’s on/off knob clockwise to close it.
5. Remove the calibration cup from the sensor face.
6. Unscrew the regulator from the calibration cylinder, then disassemble the calibration
kit as described in the Calibration section of this insert.
7. When the display reading falls below the alarm setpoints, return the controller to
normal operation.
Quarterly
Calibrate the CO transmitter as described in the Calibration section of this insert.
Troubleshooting
The troubleshooting guide describes symptoms, probable causes, and recommended
action for problems you may encounter with the CO transmitter.
NOTE: This troubleshooting guide describes transmitter problems only. See the
controller instruction manual for problems you may encounter with the
controller.
Fail Condition
Symptoms
• The controller indicates a fail condition.
Probable causes
• The transmitter wiring is disconnected or misconnected.
• The transmitter’s zero reading is low enough to cause a fail condition.
• The transmitter is malfunctioning.
Recommended action
• Verify that the transmitter wiring is correct and secure.
• Calibrate the transmitter.
• If the fail condition continues, replace the CO sensor.
• If the fail condition continues, contact RKI for further instruction.
Slow or No Response/Difficult or Unable to Calibrate
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65-2434RK CO Transmitter • 9
Symptoms
• The transmitter responds slowly or does not respond during the monthly response
test.
• Unable to accurately set the zero or response reading during the calibration
procedure.
• The transmitter requires frequent calibration.
NOTE: Under “normal” circumstances, the transmitter requires calibration once every
three months. Some applications may require a more frequent calibration
schedule.
Probable causes
• The calibration cylinder is low, out-dated, or defective.
• The transmitter is malfunctioning.
Recommended action
1. Verify that the calibration cylinder contains an adequate supply of a fresh test sample.
2. If the calibration/response difficulties continue, replace the CO sensor as described
later in this section.
3. If the calibration/response difficulties continue, contact RKI Instruments, Inc. for
further instruction.
Replacing Components of the CO Transmitter
This section includes procedures to replace the CO sensor, amplifier PCB, and charcoal
filter.
Replacing the Sensor
1. Turn off the controller.
2. Turn off or unplug incoming power to the controller.
3. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
4. Unplug the CO sensor from the amplifier PCB.
5. Remove the rubber boot and charcoal filter from the old sensor and install onto the
replacement sensor.
6. Carefully plug the replacement sensor into the socket pattern on the amplifier PCB.
NOTE: Match the sensor’s male pins with the four female sockets as you plug the sensor
into the sockets.
7. Secure the cover to the enclosure.
8. Turn on or plug in incoming power to the controller.
9. Turn on the controller.
CAUTION: Allow the replacement sensor to warm up for 5 minutes before you continue with the
next step.
10. Calibrate the replacement sensor as described in the Calibration section of this
manual.
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10 • 65-2434RK CO Transmitter
Replacing the Amplifier PCB
1. Turn off the controller.
2. Turn off or unplug incoming power to the controller.
3. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
4. Disconnect the wires from the interconnect terminal strip.
5. Unplug the CO sensor from the amplifier PCB to access one of the PCB mounting
screws.
6. Unscrew and remove the two screws that secure the amplifier PCB to the enclosure.
The screws are near the top and bottom of the amplifier PCB.
7. Remove the amplifier PCB.
8. Place the new amplifier PCB in the same position as the one you removed in step 6.
9. Use the two screws you removed in step 5 to secure the PCB to the enclosure.
10. Reconnect the wiring from the controller to the interconnect terminal strip as shown
in Table 2 and Figure 3.
11. Carefully plug the CO sensor with rubber boot and charcoal filter into the socket
pattern on the amplifier PCB.
NOTE: Match the sensor’s male pins with the four female sockets as you plug the sensor
into the sockets.
12. Secure the cover to the enclosure.
13. Turn on or plug in incoming power to the controller.
14. Turn on the controller.
CAUTION: Allow the sensor to warm up for 5 minutes before you continue with the next step.
15. Calibrate the CO transmitter as described in the Calibration section of this insert.
Replacing the Charcoal Filter
1. Turn off the controller.
2. Turn off or unplug power to the controller.
3. Remove the enclosure’s cover by unscrewing the four cover screws, one at each
corner.
4. Unplug the CO sensor from the amplifier PCB.
5. Remove the rubber boot that secures the charcoal filter to the CO sensor.
Table 2: Reconnecting the CO Transmitter to a Controller
Amplifier PCB
Interconnect Terminal Strip
Controller
Transmitter Terminal Strip
(typical)
FB 4 - 20 (FB)
+V + V (10 VDC - 30 VDC)
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65-2434RK CO Transmitter • 11
6. Remove the charcoal filter from the rubber boot.
7. Place the replacement filter in the rubber boot in the same position as the filter you
removed in the previous step.
8. Reinstall the rubber boot with charcoal filter to the CO sensor.
9. Carefully plug the CO sensor with rubber boot and charcoal filter into the socket
pattern on the amplifier PCB.
NOTE: Match the sensor’s male pins with the four female sockets as you plug the sensor
into the sockets.
10. Secure the cover to the enclosure.
11. Turn on or plug in power to the controller.
12. Turn on the controller.
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 3 to 6 months is adequate for most CO transmitter
applications. Unless experience in a particular application dictates otherwise, RKI
Instruments, Inc. recommends a calibration frequency of every 3 months.
If an application is not very demanding, for example detection in a clean, temperature
controlled environment where CO is not normally present and calibration adjustments are
minimal at calibration, then a calibration frequency of every 6 months is adequate.
If an application is very demanding, for example if CO is present often and in significant
concentrations or the environment is not well controlled, then more frequent calibration
than every 3 months may be necessary.
Calibration
This section describes how to calibrate the CO transmitter. It includes procedures to
prepare for calibration, set the zero reading, set the response reading, and return to
normal operation. It describes the test using a calibration kit that includes a calibration
cup, calibration gas, sample tubing, and a fixed flow regulator with an on/off knob. RKI
Instruments, Inc. recommends using a 0.5 LPM (liters per minute) fixed flow regulator.
NOTE: Calibrating the CO transmitter may cause alarms. Be sure to put the controller
into its calibration program or disable external alarms before continuing.
Preparing for Calibration
1. Set a voltmeter to measure in the millivolt (mV) range.
2. Remove the enclosure cover, then plug the voltmeter leads into the test points on the
amplifier PCB.
Plug the positive lead into the test point labeled CAL+; plug the negative lead into the
test point labeled CAL-.
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12 • 65-2434RK CO Transmitter
3. Use the following formula to determine the correct test points output for the
calibrating sample.
Output (mV) = (calibrating sample/fullscale) X 400 + 100
For example, with a calibrating sample of 50 PPM CO and a fullscale setting of
300 PPM, the correct output is 167 mV.
167 (mV) = (50/300) X 400 +100
4. Place the controller into its calibration program or disable external alarms.
Setting the Zero Reading
1. Screw the regulator into the zero air calibration cylinder.
2. Use the sample tubing to connect the regulator to the calibration cup.
3. Turn the regulator’s on/off knob counterclockwise to open it.
4. Hold the calibration cup against the CO sensor’s face. Leave the rubber boot and
charcoal filter on the sensor when calibrating. Hold the cup on gently to allow gas to
escape and avoid pressurizing the sensor’s sensing face.
5. Allow the gas to flow for 2 minutes.
6. Verify a reading of 100 mV (± 2mV).
7. If necessary, use the zero pot on the amplifier PCB to adjust the reading to 100 mV (±
2mV).
8. Turn the regulator’s on/off knob clockwise to close it.
9. Remove the calibration cup from the sensor face.
10. Unscrew the regulator from the zero air calibration cylinder.
11. Leave the sample tubing connected to the regulator and the calibration cup.
Setting the Response Reading
1. Screw the regulator into the calibration cylinder. Verify that the calibration gas is
representative of the transmitter’s target gas.
2. Turn the regulator’s on/off knob counterclockwise to open it.
3. Hold the calibration cup against the CO sensor’s face. Leave the rubber boot and
charcoal filter on the sensor when calibrating. Hold the cup on gently to allow gas to
escape and avoid pressurizing the sensor’s sensing face.
4. Allow the gas to flow for 2 minutes.
5. Verify that the reading matches the response reading (± 2mV) you determined earlier.
6. If necessary, use the span pot on the amplifier PCB to adjust the reading to match the
correct response reading.
7. Turn the regulator’s on/off knob clockwise to close it.
8. Remove the calibration cup from the sensor face.
9. Unscrew the regulator from the calibration cylinder.
NOTE: For convenience, leave the components of the calibration kit connected by the
sample tubing.
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65-2434RK CO Transmitter • 13
Returning to Normal Operation
1. Remove the voltmeter leads from the amplifier test points.
2. Secure the cover to the enclosure.
3. When the display reading falls below the alarm setpoints, return the controller to
normal operation.
4. Verify that the controller display reading decreases and stabilizes at 0 ppm CO.
5. Store the components of the calibration kit in a safe and convenient place.
Parts List
Table 6 lists replacement parts and accessories for the CO channel.
Table 3: Parts List
Part Number Description
06-1248RK Sample tubing (order by the foot)
07-0203RK Retaining boot (for filter)
33-7101RK Filter (charcoal)
57-0035RK-01 Amplifier PCB, CO
65-2434RK CO transmitter, complete
71-0061RK 65-2434RK CO Transmitter Manual (this document)
81-0064RK Calibration cylinder (50 PPM CO in air; 34 liter)
81-0076RK-01 Zero air calibration cylinder (34 liter)
81-1050RK Regulator with gauge and knob, 0.5 LPM, for 17 liter and 34 liter
steel calibration cylinders
81-1109RK Calibration cup
ES-1531-CO CO replacement sensor
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