RKI Instruments 65-2405RK-05 User manual

65-2405RK-05
Combustible Gas Transmitter
Operator’s Manual
Part Number: 71-0180RK
Revision: 0
Released: 2/16/11
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65-2405RK-05 Combustible Gas 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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65-2405RK-05 Combustible Gas Transmitter
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
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65-2405RK-05 Combustible Gas Transmitter
Table of Contents
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Combustible Gas Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Junction Box. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Mounting the Combustible Gas Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Wiring the Combustible Gas Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Setting the Zero Signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Replacing Components of the Combustible Gas Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Calibration Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Returning to Normal Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
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65-2405RK-05 Combustible Gas Transmitter • 1
Overview
This manual describes the 65-2405RK-05 combustible gas transmitter. This manual also
describes how to install, start up, configure, maintain, and calibrate the transmitter 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 combustible gas transmitter.
Specifications
WARNING: Do not use this product in a manner not specified in this manual.
Table 1 lists specifications for the combustible gas transmitter.
NOTE: The following symbol on the detector label is a caution to the user to refer to this
documentation for installation instructions:
WARNING: When using the 65-2405RK-05, you must follow the instructions and
warnings in this manual to assure proper and safe operation of the
65-2405RK-05 and to minimize the risk of personal injury. Be sure to
maintain and periodically calibrate the 65-2405RK-05 as described in this
manual.
Table 1:Specifications
Description Specification
Target Gas Combustible gas, methane calibration standard1
Area Classification Explosionproof for Class I, Groups B, C, and D
Sampling Method Diffusion
Signal Output 4 to 20 mA
Detection Range 0 to 100% LEL
Accuracy ± 5% of reading or ± 2% LEL (whichever is greater)
Response Time 90% in 45 seconds
Operating Temperature -40°F to 167°F (-40°C to 75°C)
1If calibration to a combustible gas other than methane is required, specify the required
calibration gas at time of order.
!
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2 • 65-2405RK-05 Combustible Gas Transmitter
Description
This section describes the components of the combustible gas transmitter. The transmitter
is a 4 - 20 mA type detector head. It consists of the combustible gas detector, amplifier, and
junction box.
Figure 1: Combustible Gas Transmitter Component Location
Combustible Gas Detector
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 mount it into the
bottom conduit hub of the junction box. A flame arrestor guard is located at the bottom of
the detector and is permanently bonded to the detector housing. The flame arrestor guard
protects the flame arrestor from impact damage. Four color-coded leads extend from the
top of the detector. The leads allow you to connect the detector to the amplifier.
PWR / SIG
WG
S2 001
SBR LEL
57-1053RK
ZERO
LEL Detector
J-Box
Controller Terminal Strip
Amplifier
SPAN
Sensor Current
mA
- Test Point
Reducing Bushing,
3/4 NPT to 1/2 NPT
Jumper Pins,
Factory Use Only
Factory Adjust Pot
Zero Pot
Span Pot
Factory Adjust Pot
+ Test Point Detector Terminal Strip
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65-2405RK-05 Combustible Gas Transmitter • 3
Amplifier
The amplifier converts the electrical output from the detector to a 4 to 20 mA signal that
corresponds to the detection range and transmits the signal to a gas monitoring controller.
A foam gasket that orients the amplifier and keeps it from rotating is installed on the
bottom of the amplifier. A label on the amplifier indicates the detector drive current. This
drive current is factory set and is dictated by the combustible gas to which the detector is
calibrated. Consult RKI Instruments, Inc. if you plan to change the calibration gas for the
transmitter, for example from a methane calibration to a hexane calibration. The amplifier
includes the detector terminal strip, controller terminal strip, span pot, zero pot, and test
points (see Figure 1).
Controller Terminal Strip
The controller terminal strip is a three position plug-in style terminal strip located near the
top of the amplifier. Use the controller terminal strip to wire the transmitter to a controller.
Detector Terminal Strip
The detector terminal strip is a four position plug-in style terminal strip located below the
controller terminal strip. Use the detector terminal strip to connect the detector to the
amplifier.
NOTE: The detector is factory-wired to the detector terminal strip. See “Wiring the
Combustible Gas Transmitter to a Controller” on page 5 for all wiring procedures
related to the transmitter.
Zero Pot
The zero pot is located in the upper left corner of the amplifier (see Figure 1). Use a small
flat blade screwdriver to turn the zero pot’s adjustment screw and adjust the amplifier’s
zero (fresh air) output during the start-up and calibration procedures.
Span Pot
The span pot is located to the right of the zero pot (see Figure 1). Use a small flat blade
screwdriver to turn the span pot’s adjustment screw and adjust the amplifier’s gas
response output during the calibration procedure.
CAUTION: The amplifier includes two additional potentiometers. They are factory-set. Do not
adjust them.
Test Points
The test points are on the left side of the amplifier (see Figure 1). The test points produce a
100 mV to 500 mV output that corresponds to the transmitter’s 4 to 20 mA output. Use the
test points and a voltmeter to measure the amplifier’s output during the start-up and
calibration procedures. The black test point in the lower left corner is the negative (-) test
point and the red test point below the zero pot is the positive (+) test point.
Junction Box
Use the junction box to install the transmitter at a mounting site that is remote from the
controller. The junction box protects the amplifier and wiring connections made to the
amplifier. Use the top 3/4’’ conduit hub to connect wiring from the amplifier to the
controller. Use the cover on the front of the junction box to access the interior of the
junction box. The detector and amplifier are factory installed in the junction box. Three
spacers installed on the back of the junction box control the distance of the junction box
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4 • 65-2405RK-05 Combustible Gas Transmitter
from a mounting surface and ensure that there is enough room to install a calibration cup
on the detector during calibration.
Installation
This section describes procedures to mount the combustible gas transmitter in the
monitoring environment and wire the transmitter to a controller.
Mounting the Combustible Gas 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. For lighter gases,
mount the detector near the ceiling; for heavier gases, mount the detector near the
floor.
Figure 2: Mounting the Combustible Gas Transmitter
2. At the monitoring site you select, hang or mount the junction box with the detector
facing down (see Figure 2).
2.70 .38
J-Box
.75
Rubber
Spacer,
3X
3/4 NPT Female
3.65
LEL Detector
3/4 x 1/2
ReducingBushing
7.5 MAX
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65-2405RK-05 Combustible Gas Transmitter • 5
Wiring the Combustible Gas Transmitter to a Controller
WARNING: Always verify that the power to the controller is off before you make
wiring connections.
1. Turn off the controller.
2. Turn off or unplug power to the controller.
3. Remove the junction box cover.
4. The detector leads are factory wired. Verify that the detector leads are wired to the
amplifier’s detector terminal strip as shown in Figure 3.
5. To gain access to a plug-in terminal strip for wiring, pull it out of its socket by
grasping the terminal strip and pulling. The detector strip is keyed so that the
controller and detector terminal strips cannot be reversed inadvertently.
WARNING: To maintain the explosion proof classification of the detector/junction box
combination, a conduit seal must be used within 18 inches of the junction
box conduit hub used for wiring to the controller.
6. Guide a three-conductor, shielded cable or three wires in conduit through the top
conduit hub of the junction box.
7. Pull out the controller terminal strip, and connect the three wires to the terminal strip
as follows (see Figure 3).
• Connect the positive wire to the PWR/SIG “+” terminal.
• Connect the signal wire to the PWR/SIG “S” terminal.
• Connect the negative wire to the PWR/SIG “-” terminal.
CAUTION: If shielded cable is used, leave the cable shield’s drain wire disconnected and
insulated at the transmitter. You will connect the opposite end of the cable’s drain
wire to the controller’s chassis (earth) ground.
8. Reinstall the controller terminal strip into its socket.
9. Secure the junction box cover to the junction box.
10. Route the cable or wires leading from the combustible gas transmitter through one of
the conduit hubs at the controller housing.
CAUTION: Do not route power and transmitter wiring through the same controller conduit hub.
The power cable may disrupt the transmission of the transmitter signal to the
controller.
11. Connect the wires to the applicable detector/transmitter terminal strip at the
controller as shown in Figure 3.
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6 • 65-2405RK-05 Combustible Gas Transmitter
Figure 3: Wiring the Combustible Gas Transmitter to a Controller
12. If shielded cable is used, connect the cable’s drain wire to an available chassis (earth)
ground at the controller. RKI controllers typically have a ground stud that can be used
to ground the cable’s drain wire.
Amplifier (Transmitter)
Black
Cable Shield
Controller or
Recording Device
+ 24 VDC
- (DC Ground)
4 - 20 mA In (S)
S
Red
White
LEL Detector
J-Box
PWR / SIG
W GR
Green Detector Wires
LEL B
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