Project Description

OM Positive Displacement Flowmeter

This range of positive displacement flowmeters offers an economical means of measuring high or varying viscosity liquids.

  • High accuracy & repeatability
  • Cost effective
  • Various rotor material options
  • Independent of viscosity
  • Quadrature pulse output option
  • Bi-directional flow
  • Optional Exd I/IIB approval (ATEX, IECEx)


OM series positive displacement flowmeters can be used to provide precise volumetric flow measurement in a broad range of industries including automotive, aviation, mining, power, chemical, pharmaceutical, food, paint and petroleum.


The positive displacement meter operates on the oval rotor principle. Two oval rotors rotate on stainless steel shafts and sweep the measuring chamber. Each revolution of the rotors measures a precise volume of liquid through the meter. This volume is independent of the viscosity and density.

Integral Instruments

Meter options include integral LCD totalisers, flow rate totalisers & batch controllers. These instruments provide monitoring & control outputs including 4~20mA, scaled pulse, alarms & batch control and are also available with robust mechanical registers:
BT LCD 5 digit reset, 8 digit cumulative totaliser.
RT12 LCD 6 digit reset, cumulative totaliser & flow rate. Analogue and Pulse Outputs
RT40 LCD 6 digit reset, cumulative totaliser & flow rate. Backlit Display
EB LCD 6 digit 2 stage batcher & cumulative totaliser.
M / V* = Mechanical registers ( see model numbering )
(Instruments also available for remote mounting and with I.S approvals)
Blind Pulse: OM P.D meters are available with reed switch & Hall Effect outputs. Quadrature pulse & Integral 4-20mA outputs are optional.


The body is available in either aluminium or stainless steel. Rotor options include stainless steel, PPS, and aluminium. Stainless steel rotors have a carbon ceramic bearing, aluminium have hardened steel roller bearings to suit more lubricous fluids. The meters come with a variety of end connections which include; BSP,NPT, Tri clamp (hygienic), ASA 150, ASA 300, PN16 , JIS.