RKI Instruments M2A Gas Transmitter
Starting at $900.00

Not in stock. Usually ships in 7-10 business days [?]

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  • LEL, O2, H2S, CO, CO2 & 100% vol CH4
  • Many toxic gases including NH3, SO2 & HCN
  • Infrared sensor for combustibles & CO2
  • Explosion proof options
  • 35 second or less response time
  • 10-30VDC operating voltage
  • 4-20mA & digital Modbus outputs
  • Available approval ratings:
    • UL, cULus, CSA, cCSAus
    • Radio frequency resistent CSA
  • 2 fully programmable alarm relays & fail relay
  • Non-intrusive calibration via magnetic wand
  • Water repellent sensor cover
  • Available as remote or direct mount
    • Remote mount includes calibration adapter

What's in the Box

  • Junction box

The RKI Instruments M2A gas transmitter operates as a stand alone gas monitor or as part of an integrated system. It connects to any controller, PLC, or DCS with an analog or digital signal. It can be calibrated externally with a magnetic wand, avoiding the need to open the housing and declassify an area for routine maintenance. Automatic zero drift correction compensates for aging sensors and ensures stable readings.

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. Toxic sensors are electrochemical type plug-in sensors, providing high specificity, fast response, and a long life. Their plug-in design allows quick replacement in the field without tools. Sensors are available for NH3, SO2, PH3, AsH3, and HCN.

Applications for the RKI Instruments M2A include petrochemical plants, refineries, water and wastewater treatment plants, pulp and paper mills, manufacturing facilities, automotive, semiconductor and chemical plants.

RKI Instruments 82-0101RK Magnetic Wand
Non-intrusive method to calibrate the M2A using a magnet to actuate magnetic control switches within the transmitter
RKI Instruments Gas Cylinder
Available in 34, 58, 103, 166 liters, steel or aluminum
RKI Instruments AC Power Supply Assembly
100VAC to 240VAC input, 24VDC output, mounted in junction box, stainless steel option
RKI Instruments Fixed Sensors
Fixed direct connect sensors available as explosion proof or non-explosion proof & with or without a junction box

Application Notes

Here's how some of our customers used this product.

O2 Level Detection

The Background: Our customer is a large metal fabricator with multiple welding booths. They seek a means of monitoring the oxygen levels inside each booth.

The Problem: The customer uses argon as a shielding gas during the welding process. Since argon can displace oxygen in the welding booth, it is important to monitor oxygen levels to ensure they are above a minimum threshold.

The Solution: We recommended the RKI Instruments M2A gas transmitter which can be used as a stand-alone gas monitor or as part of an integrated system. The M2A includes internal relays to trigger a visual or audible alarm if the oxygen levels below the preset limit.