M2A Series Stand Alone
Explosion Proof Transmitter
- Operates with or without a controller
- Direct digital readout with OLED
cold temperature display - LEL, O2, H2S, CO, CO2,
- 100% Vol CH4, and 0-9,000 PPM CH4
- Toxic Gases include NH3, SO2, HCN, and more
- 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)
The RKI M2A™ is a state-of-the-art transmitter that can operate as an independent, stand-alone monitor or as part of an integrated system. The M2A connects with an analog or digital signal to virtually any controller, PLC, or DCS. Setup procedures are simplified with user friendly push buttons and OLED menus. It utilizes a magnetic wand technique for performing non-intrusive calibration. The M2A provides an automatic zero drift correction feature, which results in more stable readings and reduces the need for adjustments due to sensor aging.
The housing of the M2A does not need to be opened for zeroing or calibration, making it unnecessary to declassify the area for routine maintenance. It is designed so that a complete field calibration can be performed by one person. Sensor construction is rated Class I, Div. 1 Groups B, C, D for flammables, CO, H2S, O2, and CO2, and Class I, Div. 2 for all other toxics.
The transmitter provides a 4-20 mA output in addition to a Modbus digital output. It also has two levels of alarms with relays, plus a fail alarm with relay. A digital display of the gas concentration, as well as alarm and status lights, can be viewed through the front window.
The toxic sensors are electrochemical type plug-in sensors, which provide high specificity, fast response, and long life. The plug-in design allows quick replacement in the field with no tools required. Toxic sensors are designed for use in Class I, Div. 2 hazardous locations. Sensors available for NH3, SO2, PH3, AsH3, and HCN.
The M2A represents the latest leading edge technology in sensor / transmitters today.
- Petrochemical plants
- Refineries
- Water & wastewater treatment plants
- Pulp & paper mills
- Manufacturing facilities
- Automotive
- Semiconductor plants
- Chemical plants
Explosion Proof
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 | ||
LEL | 65-2640RK-05 | 65-2647RK-05 | 65-2641RK-05 | |||||||||
Sensors | Catalytic | Galvanic cell | Electrochemical | Infrared | ||||||||
Measuring Ranges | 0 – 100% LEL | 0 – 9000 CH4 | 0 – 100% | 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 | 60 Seconds | 90 Seconds | 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 | ± 5% of reading or ± 2% of full scale | ± 0.5% Vol. O2 | ± 5% of | ± 5% of | ± 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 / | |||||||||||
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; | |||||||||||
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. | |||||||||||
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 | 65-2640RK | 65-2641RK UL | C CSA US | C UL US | ||||||||
65-2640RK-05 | 65-2641RK-05 | |||||||||||
Controllers | Beacon 110, Beacon 200, Beacon 410A, Beacon 800 as well as most DCS / PLC systems | |||||||||||
Warranty | One year material and workmanship | |||||||||||
Non Explosion Proof
O2 Oxygen | H2S Hydrogen Sulfide | CO Carbon Monoxide | Toxics See Chart Below | 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 | ± 0.5% Vol. O2 | ± 5% of reading or | ± 5% of reading or | ± 10% of reading or | ± 5% of reading or | |
Alarms | ||||||
Alarm Settings | Two fully programmable alarm set points, increasing / decreasing, latching / | |||||
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; | |||||
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. | |||||
Sensor | Aluminum / Plastic (non explosion proof) | |||||
Operating Environment | ||||||
Operating Temperature | -4°F to 113°F | -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 | -40°F to 122°F | |
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 | |||||
*Partial pressure sensor for helium (He) applications. Consult factory for details.
Specifications subject to change without notice.
Made in the USA
M2A Literature | |
| Product Datasheet | |
 M2A Product DatasheetSpanish M2A Datasheet | |