RKI Instruments M2A User manual

M2A Transmitter
Operator’s Manual
Part Number: 71-0305RK
Revision: R
Released: 3/10/21
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M2A Transmitter Operator’s Manual
WARNING
Read and understand this instruction manual before operating instrument.
Improper use of the gas monitor could result in bodily harm or death.
Periodic calibration and maintenance of the gas monitor is essential for proper
operation and correct readings. Please calibrate and maintain this instrument
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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M2A Transmitter Operator’s Manual
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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M2A Transmitter Operator’s Manual
Table of Contents
Chapter 1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
About the M2A Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 2: Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
External Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Internal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Chapter 3: Installation & Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Mounting the M2A Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Wiring the M2A Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter 4: Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Information Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4 - 20 mA Signal Output Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Alarm Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Chapter 5: Configuration Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Viewing & Changing M2A Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Chapter 6: Gas Type Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Selecting the Gas Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
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M2A Transmitter Operator’s Manual
Chapter 7: Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Calibration Frequency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Calibration, Combustible Gas, CO2, and Toxic Versions . . . . . . . . . . . . . . . 50
Calibration, Oxygen Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Replacing Components of the M2A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Chapter 8: RS-485 Modbus Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Wiring the M2A in a Modbus System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Using the M2A in a 4-wire Modbus System. . . . . . . . . . . . . . . . . . . . . . . . . . 64
Modbus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Supported Modbus Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Chapter 9: Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Appendix A: Control Button Quick Reference Guide. . . . . . . . . . . . . . . . . . . . . . 76
Appendix B: PLC and DCS Device Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Appendix C: Function Code 16 Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
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6M2A Transmitter Operator’s Manual
Chapter 1: Introduction
Overview
This chapter briefly describes the M2A Transmitter. This chapter also describes the M2A Transmitter Operator’s
Manual (this document). Table 1 at the end of this chapter lists the specifications for the M2A.
About the M2A Transmitter
The M2A transmitter is a fixed mount, continuous-monitoring detector head. All user adjustable parameters may
be accessed using push button switches. In addition, calibration may be performed non-intrusively by use of a
magnetic wand accessory which activates magnetic switches through a window at the front face of the detector
head.
The M2A displays the current gas reading on an OLED display which is visible through the window in the cover
(front face) and provides a 4 - 20 mA signal which indicates the target gas reading for use by a gas monitoring
controller, recording device, or programmable controller. The M2A also provides an RS-485 Modbus output.
Three sets of relay contacts, two controlled by the gas alarms and one by the fail alarm, rated at 115 VAC 5 amps
are available for controlling devices such as lights or horns or for controlling higher rated relays.
Four operating modes allow you to display and change setup and calibration settings and change the gas type.
They are Calibration Mode, Configuration Mode, Gas Type Mode, and Modbus Mode.
About this Manual
The M2A Transmitter Operator’s Manual uses the following conventions for notes, cautions, and warnings.
NOTE: Describes additional or critical information.
CAUTION: Describes potential damage to equipment.
WARNING: Describes potential danger that can result in injury or death.
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M2A Transmitter Operator’s Manual 7
Specifications
Table 1 lists specifications for the M2A.
Table 1: M2A Specifications
Target Gas/
Detection Range
Combustible Gas/Carbon Dioxide (CO2)
• Catalytic LEL: 0 - 100% LEL, 1% LEL increments (CH4calibration unless otherwise
specified. H2specific detector available)
• Catalytic CH4ppm: 0 - 9000 ppm, 20 ppm increments
• IR (infrared) CH4LEL: 0 - 100% LEL, 1% LEL increments
• IR HC LEL: 0 - 100% LEL, 1% LEL increments (propane calibration)
•IRCH
4Volume: 0 - 5.00% volume, 0.01% increments
•IRCH
4Volume: 0 - 100 % volume, 1% increments
•IRCO
2ppm: 0 - 5,000 ppm, 20 ppm increments
•IRCO
2ppm: 0 - 10,000 ppm, 20 ppm increments
•IRCO
2Volume: 0 - 5.00 % volume, 0.01% increments
•IRCO
2Volume: 0 - 50.0 % volume, 0.1% increments
•IRCO
2Volume: 0 - 100 % volume, 1% increments
Oxygen
• Oxygen (O2): 0 - 25.0 % volume, 0.1% increments
CO/H2S
• Carbon Monoxide (CO): 0 - 300 ppm, 1 ppm increments
• Carbon Monoxide (CO): 0 - 200 ppm, 1 ppm increments
• Carbon Monoxide (CO): 0 - 100 ppm, 1 ppm increments
• Hydrogen Sulfide (H2S): 0 - 100 ppm, 1 ppm increments
• Hydrogen Sulfide (H2S): 0 - 50 ppm, 0.1 ppm increments
Tox ic
• Ammonia (NH3): 0 - 75.0 ppm, 0.1 ppm increments
• Ammonia (NH3): 0 - 100 ppm, 1 ppm increments
• Ammonia (NH3): 0 - 200 ppm, 1 ppm increments
• Ammonia (NH3): 0 - 500 ppm, 1 ppm increments
• Arsine (AsH3): 0 - 1.50 ppm, 0.01 ppm increments
• Chlorine (Cl2): 0 - 3.00 ppm, 0.01 ppm increments
• Chlorine (Cl2): 0 - 5.00 ppm, 0.01 ppm increments
• Chlorine (Cl2): 0 - 10.0 ppm, 0.1 ppm increments
• Chlorine Dioxide (ClO2): 0 - 1.00 ppm, 0.01 ppm increments
• Chlorine Dioxide (ClO2): 0 - 3.00 ppm, 0.01 ppm increments
• Chlorine Dioxide (ClO2): 0 - 5.00 ppm, 0.01 ppm increments
• Hydrogen Cyanide (HCN): 0 - 15.0 ppm, 0.1 ppm increments
• Phosphine (PH3): 0 - 1.00 ppm, 0.01 ppm increments
• Sulphur Dioxide (SO2): 0 - 6.00 ppm, 0.01 ppm increments
Alarm Settings
(Alarm 1/Alarm 2)*
Ammonia (0 - 75.0 ppm and 0 - 100 ppm): 12 ppm / 25 ppm
Ammonia (0 - 200 ppm): 25 ppm / 35 ppm
Ammonia (0 - 500 ppm): 35 ppm / 300 ppm
Arsine: 0.20 ppm / 0.50ppm
Carbon Dioxide (0 - 5,000 ppm): 2,500 ppm / 5,000 ppm
Carbon Dioxide (0 - 9,000 ppm): 2,000 ppm / 5,000 ppm
Carbon Dioxide (0 - 5.00%): 0.50 % / 3.00 %
Carbon Dioxide (0 - 50.0%): 50.0% / 50.0%
Carbon Dioxide (0 - 100%): 100% / 100%
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8M2A Transmitter Operator’s Manual
Alarm Settings
(Alarm 1/Alarm 2)*,
cont’d
Carbon Monoxide (all ranges): 25 ppm / 50 ppm
Chlorine (0 - 3.00 ppm): 0.50 ppm / 1.00 ppm
Chlorine (0 - 5.00 ppm): 0.50 ppm / 1.50 ppm
Chlorine (0 - 10.0 ppm): 1.0 ppm / 3.0 ppm
Chlorine Dioxide (0 - 1.00 ppm): 0.10 ppm / 0.30 ppm
Chlorine Dioxide (0 - 3.00 ppm): 0.30 ppm / 1.00 ppm
Chlorine Dioxide (0 - 5.00 ppm): 0.50 ppm / 1.00 ppm
Combustible Gas (%LEL): 10 %LEL / 50 %LEL
Combustible Gas (0-100%Volume): 100 % / 100 %
Hydrogen Cyanide: 5.0 ppm / 10.0 ppm
Hydrogen Sulfide (0 - 50 ppm): 5.0 ppm / 10.0 ppm
Hydrogen Sulfide (0 - 100 ppm): 10 ppm / 50 ppm
Methane (ppm): 5000 ppm / 8000 ppm
Methane (0-5.00%Volume): 0.5% / 2.5 %
Oxygen: 19.5% (decreasing) / 23.5% (increasing)
Phosphine: 0.10 ppm / 0.30 ppm
Sulphur Dioxide: 1.00 ppm / 2.00 ppm
Construction (housing) Explosion-proof Junction Box, NEMA 4X
Area Classification Explosion-proof for Class I, Groups B, C, and D (Combustible, CO2, CSA Type CO and H2S,
and CSA Type oxygen)
Sampling Method Diffusion
Input Power 10 - 30 VDC
Controls • Three push button switches
• Three magnetic switches for non-intrusive calibration
Weight 4.5 lbs.
Signal Output • 4 to 20 mA with impedance maximums listed below
-12 VDC input: 500 ohms impedance max
-24 VDC input: 1000 ohms impedance max
• RS-485 Modbus
Explosion Proof Non-Explosion Proof
Operating Temperature
Catalytic LEL/ppm -40°C to 75°C N/A
Oxygen -20°C to 45°C -20°C to 50°C
H2S-40°C to 40°C -40°C to 50°C
CO -5°C to 40°C -20°C to 50°C
Toxic (ESM-01) N/A -10°C to 40°C
Tox ic (CT-7 Seri es) N/A -20°C to 40°C
Infrared Combustible -20°C to 50°C -40°C to 50°C
Infrared CO2-20°C to 50°C -40°C to 50°C
Table 1: M2A Specifications
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M2A Transmitter Operator’s Manual 9
WARNING: When using the M2A, you must follow the instructions and warnings in this manual to
assure proper and safe operation of the M2A and to minimize the risk of personal injury. Be
sure to maintain and periodically calibrate the M2A as described in this manual.
Accuracy Catalytic Combustible Gas (LEL range):
± 5% of reading or ± 2% LEL (whichever is greater)
Catalytic CH4(ppm range):
± 5% of reading or ± 50 ppm (whichever is greater)**
IR Combustible Gas/IR CO2:
± 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)
Toxic Sensors (ESM-01 Type and CT-7 Series Type):
± 10% of reading or ± 5% of full scale (whichever is greater)
*These are RKI factory settings. See “Viewing & Changing M2A Parameters” on page 42 to change the alarm settings.
**Independent of zero drift.
Table 1: M2A Specifications
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10 M2A Transmitter Operator’s Manual
Chapter 2: Description
Overview
This chapter describes external and internal components of the M2A Transmitter.
External Description
This section describes the junction box and all external components of the M2A transmitter.
Figure 1: M2A External Components
Junction Box
The M2A’s cast aluminum junction box is dust and weather resistant. The junction box also protects the M2A
and all connections made to it. Use the three 3/4 NPT conduit ports to mount the detector to the junction box
(factory installed in the bottom port) and connect wiring from an external device (left port). The top port is
shipped with a factory installed and sealed conduit plug to avoid leaks into the junction box. If necessary, the
conduit plug can be removed and the top port can be used for wiring.
WARNING: If the top conduit port is used for wiring, be sure to seal the threads to ensure water does not
enter the junction box. See “Wiring the M2A Transmitter” on page 28 for complete wiring
instructions.
Use the junction box’s two mounting holes to mount the M2A to a vertical surface at the monitoring site. The
window in the cover on the front of the junction box allows you to view the OLED display and use the magnetic
wand to actuate the magnetic control switches so you can perform non-intrusive calibration. Removing the cover
Magnetic
Wand
Junction Box Cover 3/4 NPT Conduit Port, Plugged
3/4 NPT
Conduit Port
Window
Mounting Slot (2x)
Detector
(Catalytic LEL Detector Shown)
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