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M2A-Series Fixed Gas Detector Head provided by RKI Instruments

Products > M2A Detector Head (discontinued product)

M2A Detector Head (discontinued product)

M2A LEL
M2A H2S
M2A Toxic Gas
M2A CO2
M2A H2S

Stand Alone Explosion Proof Transmitter

Please see M2A-XL for updated product line

Features

  • Operates with or without a controller
  • Direct digital readout with OLED cold temperature display
  • Available gases include
    ◦ LEL, O2, H2S, CO, CO2, and 100% Vol CH4
    ◦ Toxic gases include NH3, AsH3, Cl2, ClO2, HCN, NO2, & SO2
  • Infrared sensor for combustibles and CO2
  • 4-20 mA & digital Modbus outputs standard
  • 2 fully programmable alarm relays & fail relay
  • Non-intrusive calibration via magnetic wand
  • Explosion proof construction
  • Patented water repellent sensor cover
  • User friendly setup, push buttons & OLED menus
  • Long-life sensors (2 + years typical)
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Overview

The original M2A has been replaced with the M2A-XL Stand Alone Transmitter. The M2A-XL has an alternate housing, which is slightly taller, wider and deeper, but the electronics and operation are the same as the original M2A housing. Since this housing is deeper than the original M2A, longer standoffs are required inside to properly bring the display up to the transmitter’s window.

Changes related to using the new, alternate housing are outlined below:

  • M2A-XL is the new model name for the original M2As installed in the larger housing. The new model name is visible on the label around the display.
  • The Manual is different. The dimensional drawings have been revised to reflect the larger enclosure.
  • New part numbers are utilized for the M2A-XL. The letters “XL” are replacing the “RK” within the former M2A part #’s.
  • Inside the M2A-XL the electronics and operation are exactly the same as the original M2A.
    The only difference is the larger enclosure.
  • The original M2A has been discontinued. As a result, the original M2A sections of the current price book were removed and replaced with the M2A-XL price list sections.

For more information and ordering, please see M2A-XL Stand Alone Transmitter

Related Services

Fixed Systems Turnkey Solutions

  • Design, Consultations, and Engineering
  • Installation
  • Start-up
  • Training
  • System Maintenance

 

Application

  • Petrochemical plants
  • Refineries
  • Water & wastewater treatment plants
  • Pulp & paper mills
  • Manufacturing facilities
  • Automotive
  • Semiconductor plants
  • Chemical plants

Specifications - Explosion Proof Transmitters (Class I, Div. 1 , Groups B, C, D)

    Combustibles LEL
H2 Specific		 O2
Oxygen		 H2S
Hydrogen Sulfide		 CO
Carbon Monoxide		 CH4
Methane		 HC
Hydrocarbons		 CO2
Carbon Dioxide
LEL PPM
Part# UL 65-2640RK 65-2647RK 65-2641RK 65-2643RK-05 65-2645RK-05 65-2646RK-05 65-2649RK-CH4

65-2658RK-CH4

 65-2649RK-HC 65-2660RK-02

65-2660RK-03

65-2660RK-05

65-2660RK-10
CSA 65-2640RK-05 65-2647RK-05 65-2641RK-05
Sensors Catalytic Galvanic cell Electrochemical Infrared
Measuring Ranges 0 – 100% LEL 0 – 9000
ppmCH4		 0 – 100%
LEL		 0 – 25.0% Vol. 0 – 100 ppm 0 – 300 ppm 0 – 100% LEL

0 – 100% Vol.

 0 – 100% LEL -02 0 – 5000 ppm
-03

-05

 0 – 5% Vol.

0 – 50% Vol.
-10 0 – 100% Vol.
Resolution 1% LEL 20 ppm 1% LEL 0.1% Vol. 1 ppm 1% LEL / 1% Vol. 20 ppm / 0.01% Vol / 0.1% Vol. / 1% Vol.
Lower Detectable Limit (LDL) 2% of full scale 0.1% Vol. 2% of full scale
Max Current Draw (24VDC) 160 mA with alarm 1 and alarm 2 active and all relays energized 125 mA with alarm 1 and alarm 2

active and all relays energized

 160 mA with alarm 1 and alarm 2

active and all relays energized
Response Time (T-90) 35 Seconds or less 90 Seconds
or less		 60 Seconds
or less		 90 Seconds
or less		 30 Seconds or less
Life Expectancy 2 to 3 years with normal service 3 to 5 years with normal service 2 to 3 years with normal service 5 years plus with normal service
Accuracy
(which ever is greater)		 ± 5% of reading or ± 2% of full scale ± 0.5% Vol. O2 ± 5% of
reading or
± 2 ppm H2S		 ± 5% of
reading or
± 5 ppm CO		 ± 5% of reading or ± 2 % of full scale
Weather Resistant Patented water repellent sensor coating
Alarms
Alarm Settings Two fully programmable alarm set points, increasing / decreasing, latching /
self-resetting, on delays, off delays, normally energized or de-energized
Alarm Indication Visual LEDs. Alarm 1, Amber; Alarm 2, Red; Fail, Red
Relays 5 amp form ‘C’ contacts for alarm 1, alarm 2, and fail
Physical
Dimensions Height: 8.5” (215 mm), Width: 5.2” (132 mm), Depth: 4.5” (114 mm)
Display Alphanumeric OLED display. 8 characters per line;
2 lines for gas concentration readout, plus user-friendly calibration and setup
Enclosure Explosion proof for Class I, Div 1, Groups B, C, D.
Enclosure Rating NEMA 4X, explosion proof, watertight, cast aluminum with o-ring seal and epoxy powder coating
Controls Magnet used for calibration functions. Calibrates without opening the housing.
Internal push-button controls also available for calibration and setup
Operating Environment
Operating Temperature -40°F to 167°F

-40°C to 75°C

 -4°F to 113°F

-20°C to 45°C

 -40°F to 104°F

-40°C to 40°C

 23°F to 104°F

-5°C to 40°C

 -40°F to 122°F

-40°C to 50°C
Relative Humidity 5 – 95% RH non-condensing
Location Indoor or outdoor. Explosion proof for Class I, Div. 1, Groups B, C, D.
Operating Voltage 10 VDC – 30 VDC
Outputs
Analog Linear 4-20 mA signal, into 1000 ohms impedance max (24DC), 0 – 500 ohms max (12VDC) corresponding to 0 – full scale
Digital Modbus RTU output standard, fully configurable, 2-wire RS-485, 1200 to 19.2k baud
Approvals C CSA US
65-2640RK-05
C CSA US		 65-2641RK-05
C CSA US
Controllers Beacon 110, Beacon 200, Beacon 410A, Beacon 800 as well as most DCS / PLC systems
Warranty One year material and workmanship

Specifications - Toxic Gas Transmitters (Class I, Div. 2)

O2
Oxygen		 H2S
Hydrogen Sulfide		 CO
Carbon Monoxide		 Toxics CO2
Carbon Dioxide
Part# 65-2666RK

*65-2644RK

 65-2662RK 65-2663RK See Chart Below 65-2661RK-02

65-2661RK-03

65-2661RK-05

65-2661RK-10
Sensors Galvanic cell Electrochemical Infrared
Measuring Ranges 0-25% Vol. 0-100 ppm 0-300 ppm See Chart Below -02 0 – 5000 ppm
-03

-05

 0 – 5% Vol.

0 – 50% Vol.
-10 0 – 100% Vol.
Resolution 0.1% Vol. 1 ppm See Chart Below 20 ppm / 0.01% Vol. / 0.1% Vol. / 1%Vol.
Lower Detectable Limit (LDL) 0.1% Vol. 2% of full scale
Response Time (T-90) 35 Seconds or less 60 Seconds or less 30 Seconds or less
Max Current Draw (24VDC) 125 mA with alarm 1 and alarm 2 active and all relays energized 160 mA with alarm 1 and alarm 2 active and all relays energized
Life Expectancy 2 to 3 years with normal service 5 years plus
Accuracy
(which ever is greater)		 ± 0.5% Vol. O2 ± 5% of reading or
± 2 ppm H2S		 ± 5% of reading or
± 5 ppm CO		 ± 10% of reading or
± 5% of full scale		 ± 5% of reading or
± 2% of full scale
Alarms
Alarm Settings Two fully programmable alarm set points, increasing / decreasing, latching / self-resetting, on delays, off delays, normally energized or de-energized,
Alarm Indication Visual LEDs. Alarm 1=Amber; Alarm 2=Red; Fail=Red
Relays 5 Amp form ‘C’ contacts for alarm 1, alarm 2, and fail
Physical
Dimensions Height: 8.5” (215 mm), Width: 5.2” (132 mm), Depth: 4.5” (114 mm)
Display Alphanumeric OLED display. 8 characters per line; 2 lines for gas concentration readout, plus user-friendly calibration and setup
Sensor Rating Non explosion proof construction, designed for Class I, Div. 2, Groups B, C, D (no certification)
Housing J-Box NEMA 4X, explosion proof, watertight, cast aluminum with o-ring seal and epoxy powder coating
Controls Magnet used for calibration functions. Calibrates without opening the housing. Internal push-button controls also available for calibration and setup
Sensor Aluminum / Plastic (non explosion proof)
Operating Environment
Operating Temperature -4°F to 113°F

-20°C to 45°C

 -40°F to 104°F

-40°C to 40°C

 23°F to 104°F

-5°C to 40°C

 14°F to 104°F

-10°C to 40°C

 -40°F to 122°F

-40°C to 50°C
Relative Humidity 5 – 95% RH non-condensing
Location Indoor or outdoor
Operating Voltage 10 VDC – 30 VDC
Outputs
Analog Linear 4-20 mA signal, into 1000 ohms impedance max (24DC), 0 – 500 ohms max (12VDC) corresponding to 0 – full scale
Digital Modbus RTU output standard, fully configurable, 2-wire RS-485, 1200 to 19.2k baud
Controllers Beacon 110, Beacon 200, Beacon 410A, Beacon 800 as well as most DCS / PLC systems
Warranty One year materials and workmanship
 

 

 

 

 

 

 

 

 Part Number With J-Box Gas Range Resolution Sensor Type
65-2670RK-NH3-75 Ammonia (NH3) 0 – 75.0 ppm 0.1 ppm CT-7
65-2670-NH3-1 Ammonia (NH3) 0 – 100 ppm 1 ppm CT-7
65-2670-NH3-2 Ammonia (NH3) 0 – 200 ppm 1 ppm CT-7
65-2670-NH3-5 Ammonia (NH3) 0 – 500 ppm 1 ppm CT-7
65-2670-NO2 Nitrogen Dioxide (NO2) 0 – 15.0 ppm 1 ppm CT-7
65-2648RK-AsH3 Arsine (AsH3) 0 – 1.50 ppm 0.1 ppm ESM -01
65-2670RK-CL2-3 Chlorine (Cl2) 0 – 3.00 ppm 0.01 ppm CT-7
65-2670RK-CL2-10 Chlorine (Cl2) 0 – 10.0 ppm 0.1 ppm CT-7
65-2670RK-CLO2 Chlorine Dioxide (ClO2) 0 – 1.00 ppm 0.01 ppm CT-7
65-2648RK-HCN Hydrogen Cyanide (HCN) 0 – 15.0 ppm 0.1 ppm ESM -01
65-2648RK-PH3 Phosphine (PH3) 0 – 1.00 ppm 0.01 ppm ESM -01
65-2648RK-SO2 Sulfur Dioxide (SO2) 0 – 6.00 ppm 0.01 ppm ESM -01
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