RKI Instruments 61-1020 User manual

RKI Instruments, Inc.
www.rkiinstruments.com
61-1020/61-0230
Molecular Property Spectrometer
Combustible Gas Detector
Operator’s Manual
Part Number: 71-0592
Revision: P2
Released: 10/14/22
TM

2• 61-1020/61-0230 Molecular Property Spectrometer Combustible Gas 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. For most applications,
typical calibration frequencies are between 6 and 12 months but can
be more often or less often based on your usage.

61-1020/61-0230 Molecular Property Spectrometer Combustible Gas Detector • 3
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 two years 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:
• Absorbent cartridges
• Pump diaphragms and valves
•Fuses
•Batteries
• Filter elements
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 APARTICULAR PURPOSE. INNO
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.

4• 61-1020/61-0230 Molecular Property Spectrometer Combustible Gas Detector
Table of Contents
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
MPS Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Junction Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Mounting the Combustible Gas Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Wiring the Combustible Gas Detector to a Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Replacing the Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Calibration Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Preparing for Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

61-1020/61-0230 Molecular Property Spectrometer Overview • 5
Overview
This manual describes the 61-1020 combustible gas detector. This manual also describes how to
install, start up, maintain, and calibrate the detector when used with a gas monitoring controller. A
parts list at the end of this manual lists replacement parts and accessories for the combustible gas
detector.
The 61-1020 combustible gas detector includes a junction box. This manual may also be used for
the 61-0230 combustible gas detector which does not include a junction box and is normally
mounted in one of a controller’s conduit hubs. If you are using a 61-0230 combustible gas
detector, disregard all references to the junction box and junction box terminal block.
Specifications
Table 1 specifies the detection range and accuracy for the 14 gases that the MPS sensor can
reliably detect at the same time.
Table 1: Detection Ranges and Accuracy
Target Gas Formula Detection Range Accuracy
(0 to 50% LEL)
Butane C4H10 0 - 100% LEL ± 5% LEL
Ethane C2H60 - 100% LEL ± 5% LEL
Hydrogen H20 - 100% LEL ± 5% LEL
Isobutane HC(CH3)30 - 100% LEL ± 5% LEL
Isobutylene C4H80 - 100% LEL ± 5% LEL
Isopropanol C3H8O 0 - 100% LEL ± 10% LEL
Methane CH40 - 100% LEL ± 3% LEL
Methyl Ethyl Ketone C4H8O 0 - 100% LEL ± 5% LEL
Octane C8H18 0 - 100% LEL ± 5% LEL
Pentane C5H12 0 - 100% LEL ± 5% LEL
Propane C3H80 - 100% LEL ± 6% LEL
Propylene C3H60 - 100% LEL ± 5% LEL
Toluene C7H80 - 100% LEL ± 12% LEL
Xylene C8H10 0 - 100% LEL ± 12% LEL
NOTE: The MPS sensor will respond to other combustible gases, but the accuracy has only
been determined for these 14 gases.

6• Applications 61-1020/61-0230 Molecular Property Spectrometer
WARNING: When using the 61-1020/61-0230, you must follow the instructions and warnings
in this manual to assure proper and safe operation of the 61-1020/61-0230 and to
minimize the risk of personal injury. Be sure to maintain and periodically
calibrate the 61-1020/61-0230 as described in this manual.
Applications
The MPS combustible detector is most effective in the following applications:
• High concentrations of hydrogen sulfide (H2S) or silicones present where sensor
poisoning is a common problem
• High-humidity environments where catalytic or IR sensors may not hold up
• Environments more likely to have mixtures of hydrocarbons present
Table 2: Specifications
Target/Calibration Gas
With Junction Box
• 61-0230-CH4: Methane
• 61-0230-HC: General hydrocarbons (propane calibration standard)
Without Junction Box
• 61-1020-CH4: Methane
• 61-1020-HC: General hydrocarbons (propane calibration standard)
Area Classification Explosion-proof for Class I, Groups B, C, and D
Operating
Temperature Range
-20ºC to +50ºC (-4ºF to +122ºF)
Humidity Range 0 - 100% RH (non-condensing)
Pressure Range 80 to 120 kPa
Sampling Method Diffusion
Detection Range 0 to 100% LEL
Response Time 90% in 45 seconds
Dead Bands •Methane(CH
4): 3% LEL
• All other gases: 5% LEL

61-1020/61-0230 Molecular Property Spectrometer Description • 7
Description
The 61-1020 is a Molecular Property Spectrometer (MPSTM) type of detector which has some
advantages over a catalytic or IR type of combustible detector. The explosion-proof MPS detector
is immune to poisons, can be used in high humidity, can detect multiple gases simultaneously (see
Table 1), and does not require calibration as often as catalytic combustible sensors.
This section describes the components of the 61-1020: the MPS LEL detector and the junction
box.
Figure 1: Component Location
MPS Detector
The MPS LEL detector is made up of the MPS 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 inch
hex that allows removal or installation of the detector with a wrench. A porous flame arrestor
coated with a hydrophobic film that repels liquids is on one end of the detector and allows sample
gas to enter the detector. Four color coded leads, red, white, green, and black, extend from the
other end of the detector. Use the leads when connecting the detector to the terminal block in the
junction box.
Junction Box
The junction box allows installation of the detector at a mounting site that is remote from the
controller while protecting the detector wiring connections. Two 3/4 NPT conduit hubs allow you
to mount the detector to the junction box and connect the wiring from the detector to a controller.
The terminal block within the junction box facilitates the wiring to the detector. A cover on the
front of the junction box allows access to the interior of the junction box. Three spacers installed
on the back of the junction box control the distance of the junction box from a mounting surface
and insure that there is enough room to install a calibration cup on the detector during calibration.
J-Box
Green
Red
White
Rubber
Spacers,
3X
MPS LEL Detector
Black

8• Installation 61-1020/61-0230 Molecular Property Spectrometer
Installation
This section describes procedures to mount the combustible gas detector in the monitoring
environment and wire it to a controller.
If you purchased a 61-0230 detector that is factory installed and wired to a controller, detector
installation is not necessary, but the detector wiring can be confirmed as described in “Wiring the
Combustible Gas Detector to a Controller” on page 9.
Mounting the Combustible Gas Detector
1. Select a mounting site that is representative of the monitoring environment. Consider the
following when selecting the mounting site:
• Select a site where the detector 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 Detector
2. At the selected mounting site, hang or mount the junction box with the detector facing down
(see Figure 2).
2.70 .38
J-Box
3/4 NPT
Female
Rubber
Spacers,
3X
.75
3.65
MPS LEL Detector
7.10 MAX

61-1020/61-0230 Molecular Property Spectrometer Installation • 9
Wiring the Combustible Gas Detector 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. If the detector is mounted remotely from a controller using the junction box, proceed to
Step 4.
If the detector is mounted directly to a controller, it is normally factory wired. Confirm that
the detector’s wires are connected to the appropriate controller detector terminals and skip
to “Start Up” on page 11. See Figure 3, the controller operator’s manual, and the
controller’s detector head specification sheet for the 61-0230 detector for the wiring
connections.
4. Remove the cover from the junction box.
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. Adhere to your local electrical
code when installing the conduit seal.
5. Guide a four-conductor, shielded cable or four wires in conduit through the unused conduit
hub of the junction box. Use appropriate conduit fittings and construction technique for the
environmental rating and hazardous location classification of the junction box. The junction
box is rated NEMA 4X and classified explosion proof for Class I, Groups B, C, and D.
6. Connect the wires to the terminal block in the junction box.
CAUTION: Leave the shield drain wire insulated and disconnected at the 61-1020.
You will connect the opposite end of the cable’s drain wire at the
controller.
7. Secure the junction box cover to the junction box.
8. Route the cable or wires in conduit leading from the detector through one of the conduit hubs
at the controller. Use appropriate conduit fittings and construction technique for the
environmental rating of the controller. RKI controllers are typically rated NEMA 4X, are not
explosion-proof, and must be installed in a non-hazardous location.
CAUTION: Do not route power and detector wiring through the same conduit hub.
The power cable may disrupt the transmission of the detector signal to
the controller.
9. Connect the wires to the applicable controller terminal strip. See the controller operator’s
manual and the controller’s detector head specification sheet for the 61-1020 detector.

10 • Installation 61-1020/61-0230 Molecular Property Spectrometer
Figure 3: Wiring the Combustible Gas Detector to a Controller
10. If using a shielded cable, connect the cable’s drain wire to an available chassis ground at the
controller. RKI controllers typically have a ground stud that is a convenient grounding
location.
Red
White
Green
Black
White
Green
Red
Detector Wires
Black
Terminal Strip
J-Box
Controller
LEL
Detector
Terminals
MPS LEL Detector
Cable Shield

61-1020/61-0230 Molecular Property Spectrometer Start Up • 11
Start Up
This section describes procedures to start up the combustible gas detector and place the detector
into normal operation.
NOTE: The detector must be started up in the background gas it will operate in (i.e. fresh air or
N2).
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
operator’s manual.
3. Turn on or plug in power to the controller, then turn on the controller.
4. Verify that the controller is on and operating properly. Refer to the controller operator’s
manual.
5. Allow the combustible detector to warm up for 2 minutes before setting the zero reading.
WARNING: Do not expose the sensor to combustible gas during the 2 minute warmup
period. Exposing the sensor to gas during this period will result in a failure
condition.
Setting the Zero Reading
CAUTION: If you suspect the presence of combustible gas in the monitoring environment, use a
zero air calibration cylinder to introduce “fresh air” to the detector and verify an
accurate zero reading.
1. Verify that the detector is in a fresh air environment (environment known to be free of
combustible and toxic gases and of normal oxygen content, 20.9%).
NOTE: This manual assumes the MPS sensor is operating in a background of
fresh air. If the MPS sensor is not operating in a fresh air background,
consult RKI Instruments Inc. before zeroing the sensor.
2. Verify a reading of 0% LEL at the controller. If the display reading is 0% LEL, start up is
complete. The combustible detector is in normal operation.
If the display reading is not 0% LEL, continue to the next step.
3. Perform a zeroing operation at the controller. See the controller operator’s manual for
directions.

12 • Maintenance 61-1020/61-0230 Molecular Property Spectrometer
Maintenance
This section describes maintenance procedures. It includes details on preventive maintenance,
troubleshooting, and component replacement procedures.
Preventive Maintenance
This section describes a preventive maintenance schedule to ensure the optimum performance of
the combustible gas detector. It includes daily and biannual procedures.
Daily
Verify a display reading of 0% LEL at the controller. Investigate significant changes in the
reading.
Biannually
Calibrate the detector every six months as described in “Calibration” on page 15.
Troubleshooting
The troubleshooting guide describes symptoms, probable causes, and recommended action for
problems you may encounter with the combustible gas detector.
NOTE: This troubleshooting guide describes detector problems only. See the controller
operator’s manual for problems you may encounter with the controller.
Table 3: Troubleshooting the Combustible Gas Detector
Condition Symptom(s) Probable Causes Recommended Actions
Fail Condition • Controller indicates
a fail condition.
• The detector wiring
is disconnected or
misconnected.
• The detector zero
signal is low enough
to cause a fail
condition.
• The detector was
exposed to gas
during its 2 minute
warmup period.
• The detector is
malfunctioning.
1. Verify that the detector wiring is
correct and secure.
2. Calibrate the detector.
3. Restart the controller and ensure
that the detector’s environment is
free of combustible gas during
the warmup period.*
4. If the fail condition continues,
replace the detector.
5. If the fail condition continues,
contact RKI for further
instruction.

61-1020/61-0230 Molecular Property Spectrometer Maintenance • 13
Replacing the Detector
1. Turn off the controller.
2. Turn off power to the controller.
3. If the detector is installed in a junction box that is remote from a controller, remove the
junction box cover.
If the detector is installed directly on a controller, open the controller door.
4. For remote installations, disconnect the detector leads from the terminal block in the junction
box. Before removal, note the position of the color coded leads.
For direct installations, disconnect the detector leads from the detector terminal strip in the
controller. Before removal, note the position of the color coded leads.
5. Unscrew the detector from the controller conduit hub or junction box conduit hub.
6. Guide the detector leads of the replacement detector through the controller conduit hub or
junction box conduit hub, then screw the mounting threads of the detector into the hub.
7. If the detector is installed remotely from the controller in a junction box, use a sealant that is
designed for explosion proof installations.
If the detector is installed directly on the controller, apply any thread sealant appropriate
for the application’s environmental rating to the hub and/or detector head.
Slow or No
Response/Diffi-
cult or Unable
to Calibrate
• Unable to
accurately set the
zero or response
reading during
calibration.
• Detector requires
frequent
calibration.
NOTE: Under
“normal”
circumstances, the
detector requires
calibration once
every six months.
NOTE: Some
applications may
require a more
frequent calibration
schedule.
• The calibration
cylinder is low,
outdated, or
defective.
• The detector is
malfunctioning.
1. Verify that the calibration
cylinder contains an adequate
supply of a fresh test sample.
2. If the calibration/response
difficulties continue, replace the
detector.
3. If the calibration/response
difficulties continue, contact RKI
for further instruction.
* If a fresh air environment cannot be guaranteed, apply zero air during the warmup period.
Table 3: Troubleshooting the Combustible Gas Detector (Continued)
Condition Symptom(s) Probable Causes Recommended Actions

14 • Calibration Frequency 61-1020/61-0230 Molecular Property Spectrometer
8. If the detector is installed remotely from a controller in a junction box, connect the detector
leads to the terminal block the same way the old detector was wired (see Figure 3). See the
controller operator’s manual and the controller’s detector head specification sheet for the 61-
1020 detector to verify the connections to the controller are correct.
If the detector is installed directly on a controller, connect the detector leads to the
appropriate detector terminal strip terminals. See Figure 3 for wiring to a generic
controller. See the controller operator’s manual and the controller’s detector head
specification sheet for the 61-0230 detector for wiring specific to your controller.
9. For remote installations, reinstall the junction box cover.
For detectors connected directly on a controller, close the controller door.
10. Turn on power to the controller.
11. Turn on the controller.
12. Calibrate the replacement detector as described in“Calibration” on page 15.
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 6 months is adequate for most MPS combustible gas transmitter
applications. Unless experience in a particular application dictates otherwise, RKI Instruments,
Inc. recommends a calibration frequency of every 6 months.
If an application is not very demanding, for example detection in a clean, temperature controlled
environment where calibration adjustments are minimal at calibration, then a calibration
frequency of every 9 to 12 months is adequate.
If an application is very demanding, for example if the environment is not well-controlled, then
more frequent calibration than every 6 months may be necessary.

61-1020/61-0230 Molecular Property Spectrometer Calibration • 15
Calibration
This section describes how to calibrate the combustible gas detector. It includes procedures to
assemble the calibration kit, set the zero reading, set the response reading, and return to normal
operation.
WARNING: The controller is not an active gas monitoring device during the calibration
procedure.
NOTE: During calibration, the detector must be calibrated with a cylinder of methane in a
background of real air containing argon and CO2. Only use the RKI-provided
calibration cylinder 81-9070RK-03.
NOTE: This manual assumes the MPS sensor is operating in a background of fresh air. If
the MPS sensor is not operating in a fresh air background, consult RKI
Instruments Inc. before calibrating the sensor.
Materials
Before calibration of the detector, the following items are required:
• a zero air calibration cylinder provided by RKI Instruments Inc.
•aCH
4calibration cylinder (in a background of real air which contains argon and CO2)
• a 0.5 LPM fixed flow regulator with an on/off knob
• a calibration cup for the detector
• short piece of sample tubing to connect the regulator to the calibration cup
Preparing for Calibration
1. Screw the calibration cup onto the detector.
2. Use the sample tubing to connect the regulator to the calibration cup.
3. Place the controller into its calibration program or disable external alarms.
NOTE: Calibrating the combustible detector may cause alarms. Be sure to put the
controller into its calibration program or disable external alarms before
continuing.

16 • Calibration 61-1020/61-0230 Molecular Property Spectrometer
Setting the Zero Reading
CAUTION: If you suspect the monitoring environment is not free of combustible vapors, use the
calibration kit and a zero air calibration cylinder to introduce “fresh air” to the
detector and verify an accurate zero setting
1. To calibrate the unit for fresh air monitoring, ensure that a zero air calibration cylinder is used
to set the zero reading.
2. Allow the combustible detector to warm up for at least 2 minutes.
WARNING: Do not expose the sensor to combustible gas during the 2 minute warmup
period. Exposing the sensor to gas will result in a failure condition.
3. Follow the directions in the controller’s operator’s manual for setting the zero reading.
Setting the Response Reading
1. Follow the directions in the controller’s operator’s manual for setting the response reading
(span).
2. When the directions call for exposing the detector to gas, screw the regulator into the
methane in real air cylinder provided by RKI Instruments Inc.
3. Turn the on/off knob counterclockwise to open the regulator.
4. Allow the gas to flow to the detector for 1 minute before continuing with the directions.
5. After setting the response reading, turn the on/off knob clockwise to close the regulator,
unscrew the regulator from the cylinder and remove the calibration cup from the detector.
6. Allow the reading at the controller to decrease below the alarm points before returning the
controller to normal operation or enabling external alarms.
NOTE: If you do not allow the gas reading decrease below the alarm points, then
unwanted alarms may occur.
7. Verify that the controller display reading decreases and stabilizes at 0% LEL.
8. Store the components of the calibration kit in a safe and convenient place.

61-1020/61-0230 Molecular Property Spectrometer Parts List • 17
Parts List
Table 4 lists replacement parts and accessories for the 61-1020 combustible gas detector.
Table 4: Parts List
Part Number Description
18-0400RK-01 Junction box with spacers
61-0230 MPS LEL detector
71-0592 61-1020/61-0230 Combustible Gas Detector Operator’s Manual (this document)
81-1050RK Regulator, with gauge and knob, 0.5 liter/minute continuous flow, for 17 liter
and 34 liter steel calibration cylinders (cylinders with external threads)
81-1051RK Regulator, with gauge and knob, 0.5 liter/minute continuous flow, for 34 liter
aluminum/58 liter/103 liter calibration cylinders (cylinders with
internal threads)
81-1103RK Calibration cup
81-9070RK-03 Calibration cylinder, 50% LEL methane in air, 103 liter
81-F076RK Cal kit: 103 liter cylinder of 50% LEL CH4 in air, 0.5 LPM fixed flow regulator
with gauge and knob, calibration cup, and 3 feet of calibration tubing