RKI Instruments 65-2432RK User Manual

65-2432RK

Carbon Monoxide Transmitter

Operator’s Manual

Part Number: 71-0070RK
Revision: P1
Released: July 8, 2001

RKI Instruments, Inc.

1855 Whipple Road

Hayward CA 94544

Phone: [phone] Fax: [phone]

Product W arranty

RKI Instruments, Inc., warrants 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:

a) Absorbent cartridges d) Batteries
b) Pump diaphragms and valves e) Filter elements
c) Fuses

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.

65-2432RK CO Transmitter • 2

Table of Contents

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

CO Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Junction Box. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Mounting the CO Transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Wiring the CO Transmitter to a Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Setting the Zero Signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Replacing Components of the CO Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Returning to Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

65-2432RK CO Transmitter • 3

Overview

This manual describes the 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.

Table 1: Specifications

Target Gas Carbon Monoxide (CO)
Area Classification Explosionproof for Class I, Groups B, C, and D
Input Voltage 11 VDC - 30 VDC
Sampling Method Diffusion
Signal Output 4 to 20 mA
Detection Range 0 to 300 PPM (parts per million)
Response Time 90% in 30 seconds

65-2432RK CO Transmitter • 4

Description

This section describes the components of the CO transmitter. The transmitter consists of
the CO detector, amplifier, and junction box.

Test Point (-)

Factory Set
Potentiometer

Zero Potentiometer

Span Potentiometer

Jumper Block Installed To

Toxic Select Header

Detector Terminal Strip

Carbon Monoxide Detector

CO Detector

3/4" Conduit Hub

Interconnect Terminal
Strip

Test Point (+)

Carbon Monoxide
Amplifier

Securing Screw (2)

Detector Housing

CapGasket

Detector Housing
Cap

Flame Arrestor

Figure 1: CO Transmitter Component Location

The CO detector includes the detector housing and sensor.

Detector housing

The detector housing protects the sensing components within the housing. Use the
mounting threads at the top of the housing to screw the CO detector into the bottom
conduit hub of the junction box. Use the removable cap near the bottom of the housing to
access the sensor for maintenance or replacement. The cap protects the sensor from
damage and includes a flame arrestor which contains any sparks which may occur
within the detector housing. A cap gasket seals the interface between the housing and
cap.

Two wires extend from the top of the detector housing. Use these wires to connect the CO
detector to the amplifier. The housing includes a four-socket pattern. This socket
pattern accepts the sensor’s four pins to secure the sensor within the detector housing. A
pre-amplifier, located between the sockets and two interconnect wires, conditions the
sensor’s signal before the signal reaches the amplifier.

Sensor

The sensor is secured within the sensor housing by the four pins. Through a series of
chemical and electrical reactions, the sensor produces an electrical output that is
proportional to the detector range of the transmitter.

65-2432RK CO Transmitter • 5

Charcoal Filter

The disc-shaped charcoal filter is secured to face of the CO sensor with a rubber boot.
The charcoal filter prevents interference gases (hydrogen sulfide [H

S] and certain

2

hydrocarbons) from producing false CO readings.

Amplifier

The amplifier 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 includes the amplifier type selector, detector terminal strip,
interconnect terminal strip, span potentiometer, zero potentiometer, and test points (see
Figure 1.)

Amplifier type selector

The amplifier type selector is near the bottom left corner of the amplifier. It is to the
left of the detector terminal strip and below the span potentiometer.

The amplifier included with the CO transmitter is designed for use with RKI’s toxic gas
and oxygen transmitters. The amplifier type selector determines for which transmitter
the amplifier is intended. For CO transmitters, a jumper block is installed over the

TOXIC selector (see Figure 1.)

Detector terminal strip

The detector terminal strip is the four-point terminal strip near the bottom of the
amplifier. Use the detector terminal strip to connect the CO detector to the amplifier.

NOTE: The CO detector is factory-wired to the amplifier. See the Installation section

of this manual for all wiring procedures related to the transmitter.

Interconnect terminal strip

The interconnect terminal strip is the four-point terminal strip near the top of the
amplifier. Use the interconnect terminal strip to connect the amplifier to a controller.

Span potentiometer

The span potentiometer is on the left side of the amplifier. Of the three potentiometers,
the span potentiometer is bottom most. Use the span potentiometer to adjust the
transmitter’s response output during the calibration procedure.

Zero potentiometer

The zero potentiometer is above the span potentiometer. Use the zero potentiometer to
adjust the transmitter’s target gas-free output during the start-up and calibration
procedures.

CAUTION: The third potentiometer is factory-set. Do not adjust it.

Test points

The test points (labeled TP- and TP+ ) are on the left and right side of the interconnect
terminal strip. The test points produce a 100 to 500 mV output that is proportional to the
transmitter’s 4 to 20 mA output. Use the test points and a voltmeter to measure the
transmitter’s output during the start-up and calibration procedures.

65-2432RK CO Transmitter • 6