In-Situ Oxygen and Combustibles (COe) Transmitter

Superior Design for Superior Results!

  • Combination of O2 and COe for ideal combustion efficiency
  • Real-time measurements
  • Unique, heated solid electrolyte combustibles sensor
  • Easy access to sensors for fast and simple service

The MRU OMS 420 Series Transmitters are offered in four different versions: Compact, Remote mount, High-temp, or Ex for hazardous locations.  The OMS 420’s are  the ideal choice to optimize fuel efficiency on combustion sources, with a number of advantages over other transmitters.

  • The addition of our unique combustibles sensor allows safe operation with a lower Excess Air Ration, translating in to higher efficiencies
  • The MRU Combustibles Sensor is accurate and stable even down to 1% oxygen – No dilution is needed.
  • The Flow Guidance Tube design allows the sensor to be mounted near the back of the transmitter to make service fast, easy, and no need for system shutdown.
  • Mounting versatility
  • Available Auto Calibration

Better sensors and design for better performance and reliability

  • Zirconium dioxide O2 sensor has long life, fast response, high stability & low energy consumption
  • Heated Solid Electrolyte COe sensor has high accuracy/sensitivity, fast response, long life, and stable down to 1% oxygen -No dilution air required,
  • Flow Guidance Tube allows easy access to the sensors and are suitable for high dust / particulate or high temperature applications to 3000°F with probe lengths to 6′
  • Optional Auto Calibration
Measuring ranges
COe – Combustibles 0 … 1,000 ppm COe (combustibles gas)
O2 – Oxygen 0.1 … 25 % (user defined analog output range)
Dimensions and other data
Transmitter outputs Two (2) 4/20mA and RS485 (Modbus)
Flange DN65 PN6, Ø 6.5″ (165 mm) for Compact & RT

4″ 150lb ANSI for HT;

4″ 150lb ANSI Flange Adapter for Compact & RT


Response time T90 < 10 seconds
Power supply 18-24VDC; 90-100 W
Protection class IP 65
Weight > 33lbs (15 kg), depending on probe tube size

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