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65-2434RK
Carbon Monoxide Transmitter
Operator’s Manual
Part Number: 71-0061RK
Revision: D
Released: 2/16/11
www.rkiinstruments.com
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WARNING
Read and understand this instruction manual before operating
detector . Improper use of the dete ctor 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.
T ypical calibration frequencies for most applications a re between
3 and 6 months, but can be required more often or less often
based on your usage.
65-2434RK CO Transmitter
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Product Warranty
RKI Instr umen ts, I nc. wa rran ties gas a larm equi pment sold by us to be fr ee f rom def ects in
materials, workmanship, and performance for a period of one year fr o m date of shipment
from RKI Instruments, Inc. Any parts found defective withi n tha t 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 ser v ice, and
which must be cleaned, repaired, or replaced on a routine basis. Examples of such items
are:
W arranty 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 , a nd we are not r esponsible for removal or r eplacement costs,
local repair costs, transportation costs, or contingent expenses incurred without our prior
approval.
a) Absorbent cartridges d) Batteries
b) Pump diaphragms and valves e) Filter elements
c) Fuses
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 RK I 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 i ndemnification for any accident or dama g e ca u s e d by the operation of
this gas monitor, and our warranty is limited to the replacement of parts or our complete
goods.
65-2434RK CO Transmitter
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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
65-2434RK CO Transmitter
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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 transm itter.
Specifications
Table 1 lists specifications for the CO transmitter.
Table 1: Specifications
Target Ga s Carbon monoxi de (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
W ARNING: 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 period ically
calibrate the 65-2434RK as described in this manual.
65-2434RK C O T r an s mi tt e r • 1
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Description
Terminal Strip
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.
Enclosure
(shown w/out cover)
Amplifier PCB
Amplifier PCB Mounting
Screw (under sensor)
Sensor (w/charcoal
Test Point
CAL+
Interconnect
CA L+
TB1
R
+V
FB
B
CA L-
ZER O
SPAN
filter & boot)
Factory Set Pot
Test Point CAL-
Zero Pot
Span Pot
Amplifier PCB
Mounting Screw
Cable Bushing
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 enclosur e 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 [H
S] and cert ain
2
hydrocarbons) from producing false CO readings.
Amplifier PCB
The amplifier PCB converts the electrical output from th e sensor to a 4 to 20 mA signal
(that is proportional to the detection range) and transmits the sig na l 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).
2 • 65-2434RK CO Transmi tter