Differential fuel flow meter DFM Fuel consumption measurement on EURO 3/4/5 diesel engines.

Differential fuel flow meter DFM is designed for diesel fuel consumption measurement in the fuel line of vehicles and installations.

Differential fuel consumption meter DFM may be used both with vehicle tracking system and fuel monitoring system installed on motor vehicles with modern EURO (TIER) 3/4/5 diesel engines.

Differential fuel meter DFM is used to measure the fuel consumption of vehicles, where it is not possible to apply the single-chamber diesel meter and the installation scheme with the return fuel line ringing.

Differential_fuel_meter (1)




There are two realizations of the differential fuel flow meter, which differ in measuring chambers volume. They are designed for different maximum flow rates measurement.

Model   Chamber volume, ml   MIN flow rate in each chamber, l/h   MAX flow rate in each chamber, l/h
DFM 250D   12.5   25   250  
DFM 400D   20   50   400

Operating Principle

The operating principle of differential diesel meters is to calculate the fuel consumption as a difference between the flow rates in supply and return fuel lines of the engine.

Differential fuel consumption meter DFM consists of two three-dimension ring type measuring chambers. Each chamber generates the impulse, when the volume of fuel (which is equal to the measuring chamber volume) passes through it. Electronic scheme is responsible for the impulses deduction and output impulses formation. For the 1 liter of consumed fuel DFM generates the number of impulses, which is marked on the meter harness.


Differential fuel flow meter is mounted into the fuel line of a vehicle without changing the fuel system scheme.

Differential diesel meter DFM can operate with GPS trackers which have discrete or pulse input 0-32V, for example, with data logger CKPT 31 Lite, vehicle tracking device CKPT 45.


Choosing the differential fuel flow meter for internal combustion engine

Engine power, кW   Recommended DFM models   Recommended mounting kits
up to 200   DFM 250D   DIFF-01, №4
200 - 350   DFM 400D   DIFF-01, №4


Warranty period for  logo_DFM_S(1) fuel flow meters is 18 months from the date of installation or 24 months from the date of manufacturing.