Microsensorcorp MDM491 Piezoresistive Differential Pressure Transmitter

Microsensorcorp MDM491 Piezoresistive Differential Pressure Transmitter is a compact full-welded (no sealed ring) differential measurement element. Silicon oil is filled in between the die and two diaphragms, when the measured differential pressure is added on two diaphragms, the pressure could be transferred onto the die through silicon oil.

Sensor die connects with amplifier circuit through wires, using semiconductor piezoresistive effect, transforming differential pressure signal into an electric signal. The output signal from Weston Bridge on the sensing die has a good linear relationship with differential pressure, so the measured differential pressure could be measured precisely.

The whole product is used for differential pressure measurement of various gases and liquids in the pipeline in many fields including petroleum, chemical industry, power station, and hydrology, etc

Microsensorcorp MDM491 Features

  • Full stainless steel construction, compact size, easy installation;
  • Welding and fully-sealed construction; housing protection IP65;
  • Using piezoresistive differential pressure sensor, 316L isolated diaphragm;
  • Temperature compensation and aging, stable performance;
  • Zero and span adjustable outside for plug connection version.


  • Industrial process control
  • Differential pressure measurement
  • Gas, liquid pressure measure
  • Pressure checking meter
  • Pressure calibrator
  • Ventura and eddy-current flow meter

Electrical Performance

  • Power Supply: 15V~28V DC
  • Output Signal: 4mA~20mA DC(2-wire); 0V/1V~5V/10V DC, 0mA~10mA/20mA DC(3-wire)
  • Electrical Connection: plug or cable
  • Response Time: (10%~90%): ≤1ms
  • Insulation Resistance: 100MΩ, 50VDC

Construction Performance

  • Housing: SS 1Cr18Ni9Ti
  • Diaphragm: SS 316L
  • Filled liquid: silicon oil

Microsensorcorp MDM491 Specifications

Range Code 0A 02 03 07 08 09 10 12
Unit KPa MPa
Pressure Range 0~35 0~70 0~100 0~200 0~350 0~700 0~1 0~2
+overpressure 70 150 200 400 700 1400 2.0 4.0
-overpressure 35 70 100 200 350 700 1.0 1.0
Static Pressure ≤20MPa


  1. We suggest to install a tri-valve between the measured point and transmitter to protect the media adding on the transmitter’s positive and negative cavities slowly;
  2. We suggest to make two pressure ports horizontally to reduce the installation direction effect;
  3. Please pay attention that the static pressure should be less than 20MPa, transmitter positive and negative cavity should be in the rating pressure range;
  4. Digital indicator information, please refer to MPM480 datasheet;
  5. If the user has a special requirement, please feel free to contact our

Download Datasheet: MDM491, Microsensorcorp-Piezoresistive Differential Pressure Transmitter

Ref: Microsensorcorp.com