M921 Precision Electromagnetic Flow Meter

Modernized M920: Dot-matrix display, larger datalogger memory, easier access, maintenance, installation. Extensive functionality and 0.25% accuracy remained the same.

  • Large DM display, easily accessible
  • 0.25% accuracy, wider flow range
  • Empty pipe detection, temperature measurement
  • Datalogger (900000 records), dosing, self-diagnostic
  • 7 different I/O interfaces + Modbus protocol

M921 Precision Electromagnetic Flow Meter accurately measures flow of conductive liquids from 5 µS up. As there are no moving parts in the flow profile the flow meter can be applied to measure extremely polluted liquids containing even solid pollution. Evaluation and readout unit (transmitter) indicates both positive and negative flow as well as total and custom volume counters. Logged data can be shown on display or downloaded via RS232 or RS485 with Modbus protocol. Ex921 sensor for use in potentially explosive atmospheres in category II 3G EEx nA II T5/T6 is available in remote version of the flow meter.

Model-specific features

M921 is similar to M920 in terms of 0.25% accuracy, empty pipe and electronics diagnostic, liquid temperature measurement through excitation coils, I/O ports, datalogger and other functions. Thanks to modernized design, the M921 is now much easier to operate and maintain. It has 6 buttons, large dot-matrix display, customizable screen elements, easy-to-use clamp opening mechanism and more mounting options. Datalogger memory increased by factor of 60.

Typical applications

M921 with its high accuracy is ideal for critical applications in chemical, pharmaceutical or food industry. Providing wide range of outputs, the M921 can be used in other areas such as paper, water, waste-water, etc.

Flow (liquid) 0.03 - 12 m/s
accuracy 0.25%
Temperature -20°C - 150°C, measuread at excitation coils


Frequency (out) 0 - 12 kHz
Pulse (out) ≥ 5 ms
Relay switch (out) max. 110 V, 1 A, 30 W
Current loop (out) 4 - 20 mA
Serial bus (both) USB (RS232), RS485 with Modbus
Digital switch (in) 0 / 5 - 30 V