RKI 65-2481RK User manual

RKI Instruments, Inc.
www.rkiinstruments.com
65-2481RK
Multi Point Detector
Operator’s Manual
Part Number: 71-0204RK
Revision: A
Released: 8/2/11

65-2481RK Multi Point Detector
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.

65-2481RK Multi Point Detector
Product Warranty
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:
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

65-2481RK Multi Point Detector
Table of Contents
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Detectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Conduit Seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Junction Box. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Mounting the Multi-Point Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Wiring the Multi-Point Detector to a Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Setting the Zero (Fresh Air) Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Replacing Components of the Multi-Point Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Calibration, LEL, H2S and CO Detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Returning to Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Calibration, Oxygen Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Setting the Fresh Air Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Returning to Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

65-2481RK Multi Point Detector • 1
Overview
This manual describes the 65-2481RK multi point direct connect detector. This manual
also describes how to install, start up, maintain, and calibrate the detector when it is used
with a gas monitoring controller. A parts list at the end of this manual lists replacement
parts and accessories for the detector.
Specifications
WARNING: Do not use this product in a manner not specified in this instruction
manual.
Table 1 lists specifications for the multi-point detector.
Table 1: Specifications
Target Gas 65-2481RK: LEL/O2/H2S/CO, methane calibration standard for
LEL
65-2481RK-01: LEL (IR CH4)/O2/H2S/CO, methane calibration
for LEL
65-2481RK-02: LEL (IR HC)/O2/H2S/CO, propane calibration for
LEL
*Note: Since the 65-2481RK is a direct connect detector, the
calibration is done at the controller.
Area Classification Explosion proof for Class I, Groups B, C, and D
Sampling Method Diffusion
Detection Range LEL: 0 to 100 %LEL (lower explosive limit)
O2: 0 to 25 %volume
H2S: 0 to 100 ppm (parts per million)
CO: 0 to 300 ppm (parts per million)
Response Time 90% in 30 seconds
Accuracy Catalytic Combustible Gas:
± 5% of reading or ± 2% LEL (whichever is greater)
IR Combustible Gas:
± 5% of reading or ± 2% of full scale (whichever is greater)
Oxygen:
± 0.5% O2
Hydrogen Sulfide:
± 5% of reading or ± 2 ppm H2S (whichever is greater)
Carbon Monoxide:
± 5% of reading or ± 5 ppm CO (whichever is greater)
Operating Temperature 23°F to 104°F (-5°C to 40°C)

2 • 65-2481RK Multi Point Detector
NOTE: The following symbol on the detector label is a caution to the user to refer to this
documentation for installation and operation instructions:
WARNING: When using the 65-2481RK, you must follow the instructions and warnings
in this manual to assure proper and safe operation of the 65-2481RK and to
minimize the risk of personal injury. Be sure to maintain and periodically
calibrate the 65-2481RK as described in this manual.
!

65-2481RK Multi Point Detector • 3
Description
This section describes the multi-point detector. It consists of the detectors, the terminal
strips, the conduit seal, and the junction boxes.
Detectors
This section describes the components of the various detectors that are used with each
model of the 65-2481RK.
61-0140RK LEL Detector
Figure 1: 61-0140RK LEL Detector Component Location
The combustible gas detector is a catalytic type detector that produces an electrical output
that corresponds to the detection range. It is packaged in a 1/2 inch NPT nipple with a
sintered metal flame arrestor on one end allowing ambient air to diffuse into the detector.
The flame arrestor also contains any sparks which may occur within the detector. The 1/2
inch NPT mounting threads at the top of the detector allow you to install it in the bottom
conduit hub of the junction box with the use of a 3/4 in. x 1/2 in. NPT reducer. A
rainshield screws onto the bottom of the detector (flame arrestor end). The rainshield
helps protect the detector from rain and debris in the monitoring environment. Four color-
coded leads extend from the top of the detector. The leads allow you to connect the
detector to the terminal block.
LEL Detector

4 • 65-2481RK Multi Point Detector
61-0190RK IR LEL Detector
Figure 2: 61-0190RK IR LEL Detector Component Location
The infrared LEL detector is made up of a miniature infrared combustible gas LEL
detector housed and encapsulated in a pipe nipple. The pipe nipple has 3/4” NPT threads
on each end and a 1 1/4” hex that allows removal or installation of the detector with a
wrench. A porous flame arrestor that is coated with a hydrophobic film that repels liquids
is on one end of the detector and allows sample gas to enter the detector. The flame
arrestor also contains any sparks which may occur within the detector. Four color coded
leads, red, white, green, and black, extend from the other end of the detector. The leads
allow you to connect the detector to the terminal block. To distinguish the propane
detector from the methane detector (in case the replacement sensor label that is applied to
one of the leads is lost), a short length of red shrink tubing is applied to the white wire of
the propane detector near where the wire comes out of the nipple.
IR LEL Detector

65-2481RK Multi Point Detector • 5
Oxygen Detector
The detector consists of the oxygen sensor, the detector housing body, detector housing
cap, and cap gasket.
Figure 3: Oxygen Detector Component Location
Detector Housing Body
The detector housing body protects the electronic components within the housing. Use the
mounting threads at the top of the housing to screw the oxygen detector into the 3/4”
NPT hub on the bottom of the junction box. Two wires extend from the top of the detector
housing body. Use these wires to connect the oxygen detector to the terminal block. One of
the wires is white and one of the wires is green.
The housing includes two sockets installed on a circuit board. These sockets accept the
plug-in sensor’s two pins to provide electrical connection for the sensor. The circuit board
with the sockets conditions the sensor’s signal before the signal reaches the controller.
Housing Cap & Cap Gasket
The housing cap screws onto the detector housing. It retains the plug-in sensor and
protects it from damage. A foam gasket is installed inside the housing cap that seals
against the sensor face. The housing cap also includes a flame arrestor which contains any
sparks that may occur within the detector and a flame arrestor guard which protects the
flame arrestor from damage. Unscrew the detector cap to access the plug-in sensor for
maintenance or replacement. A cap gasket seals the interface between the housing and
cap.
Plug-in Oxygen Sensor
The plug-in sensor is secured in the detector assembly by the housing cap. It has two pins
that mate with the sockets in the detector housing body. Through a series of chemical and
electrical reactions, the sensor produces an electrical output that corresponds to the
detection range of the transmitter.
Detector Housing Body
Detector Housing Cap
Flame Arrestor
Guard
Plug-in Oxygen Sensor
Cap Gasket

6 • 65-2481RK Multi Point Detector
CO Detector
The detector consists of the CO sensor, charcoal filter with rubber boot, detector housing
body, detector housing cap, and cap gasket.
Figure 4: CO Detector Component Location
Detector Housing, Housing Cap, & Cap Gasket
The detector housing body protects the sensing components within the housing. Use the
3/4” NPT 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.
A flame arrestor guard is permanently bonded to the cap.
Two wires extend from the top of the detector housing body. Use these wires to connect
the CO detector to the multi-point detector. 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 controller.
Plug-In Sensor
The sensor is secured within the sensor housing by the housing cap. It has four pins that
mate with the sockets in the detector housing body. Through a series of chemical and
electrical reactions, the sensor produces an electrical output that corresponds to the
detection range of the detector.
Charcoal Filter
The disc-shaped charcoal filter is secured to the face of the CO sensor with a rubber boot.
The charcoal filter prevents interference gases (hydrogen sulfide [H2S] and certain
hydrocarbons) from producing false CO readings.
Plug-In CO Sensor
Rubber Boot With
Charcoal Filter
Detector Housing Cap
Detector Housing Body
Cap Gasket
Flame Arrestor
Guard