Aquametro Contoil VZD, VZP & DFM Fuel Meters

Fuel Consumption Measurement
For Trucks. Buses, Trains, Construction & Agricultural Machinery, Small Boats and Generators

The best choice to control you fuel consumption for trucks, buses, trains, construction and agricultural machinery, small boats, and generators.

Features & Benefits

Quick and Easy Installation in Vehicles of Every Type
Supports Most Used Models
Short Down-time (Off-operation) Period
Proved and Tested System
Easy and Accurate Reading of Engine Fuel Consumption
No Extra Maintenance Necessary
Tamper-proof Measurement
Low Installation Costs
Quick and Easy Installation
Quick Pay-back Period

How to Measure Fuel – Two Systems: Direct and Differential Consumption)

Direct Consumption
Differential Consumption
Fuel Oil Info
Pressure Drop Curves
Savings Examples

Measure Fuel by Direct Consumption

With this variant, the fuel is sucked out of the tank by the pump and through the preliminary filter, then fed through the fine filter to the mechanical injection pump. Depending on the engine conditions, the injection pump measures the fuel to be injected and forwards it to the individual cylinders. There, the fuel is injected into the combustion chamber by the injection nozzles. The unused fuel is not fed back to the tank through a separate line, but is fed back into the fuel line after the pump and before the fine filter in order to filter out any mechanical impurities. In this variant, the pump supplies the amount of fuel required by the engine, depending on its operating mode. The pump supply is controlled by the pressure after the pump.

Measure Fuel by Differential Consumption

With this variant, the fuel is sucked out of the tank by the pump and through the preliminary filter, then fed through the fine filter to the mechanical injection pump. Depending on the engine conditions, the injection pump measures the fuel to be injected and forwards it to the individual cylinders. There, the fuel is injected into the combustion chamber by the injection nozzles. The pump's job is to provide 4 to 10 times the amount of fuel that could possibly be used (e.g., for a maximum consumption of 50 l/h, the pump should be able to supply 200 l/h to 500 l/h). This quantity depends on the engine and the manufacturer; the above figures are just guidelines. The unused fuel is returned back to the tank through a separate line. This is the standard in modern engines (common rail, etc.).

Our fuel flow meters are manufactured to run according to the fuel oil specification in the norm ISO 8217-2010. This norm specifies the characteristics of the fuel. Fuel oil with low sulfur can be used if it follows the rules specified in the mentioned norm. A few parameters from this norm are listed in the table below...

Fuel Information

*) Diesel, diesel oil or AGO (Automotive GasOil) are the same
**) Also used for river boats
***)Max. value – normally, the value is much lower

Viscosity Information

Kinematic viscosity – Stokes, Centi-Stokes, mm2/s – St, cSt, mm2/s
Dynamic viscosity – Poise, Centipoise (outmoded) – P, cP

Conversion – cSt 3 density = mPa.s
Engler degrees °E to mPa.s: only use conversion table
Saybolt units to mPa.s: only use conversion table
Redwood units to mPa.s: only use conversion table

Rule of Thumb – 1 cSt ~ 1mm2/s ~ 1mPa.s

Contoil VZD 4, VZP 4

Contoil VZD 8, VZP 8, DFM 8D, DFM 8S, DFM 8EDM, DFM 8ECO, DFM 12ECO

Contoil DFM 20S

Contoil DFM 25S

Viscosity Diagrams

A = 5 mPa.s
B = 50 mPa.s
C = 100 mPa.s
D= 200 mPa.s
E = 500 mPa.s

For a pressure drop of more than 1 bar, it is recommended to use the next larger meter size. Maximum permissible pressure drop = 3 bar

Example for Trucks

Below are examples on how easy it is to calculate what this system is worth to you...

Examples of Operating Data of Vehicle

Average price of diesel fuel in Europe
DFM 8D used for this example. Complete investment cost may vary from country to country due to local situations.
Includes flow sensors, board computer, all transport and import costs, installation and start-up of system.

Take the example from the third column: with the above vehicle operating data and 10% estimated reduction of fuel cost, the investment will pay back its costs after only three months. Since the figures are different in each area, they have to be adapted to individual values. Ask your authorized dealer for a personal assessment. He will calculate your possible cost savings based on your vehicle data, operating conditions and the local cost situation.

VZD / VZP System – Suitable for Small Engines

Contoil VZD 4 – Tech Data & Specs Here

The easy way to find your fuel consumption. Just install it and read the values on the display (total, trip, current consumption and more).

Contoil VZP 4 – Tech Data & Specs Here

If the installation place is hidden and a read-out on the flow meter not possible, than this flow meter is the right one. Connect it to the Contoil VZD CU and you will have all the necessary information wherever you want it.

Suitable for large engines

Contoil VZD 8 – Tech Data & Specs Here

An easy way to find your fuel consumption. At a glance, you have the following information: total, trip, actual fuel consumption and much more. With its digital output, the results can be transferred to a remote host.

Contoil VZP 8 – Tech Data & Specs Here

For installation places where the read-out is not easy, choose this flow meter. The built-in LED gives you the function status at any time. The VZD CU is recommended for fuel calculation.

Connection to a remote calculator is possible (e.g., fleet manager).

Suitable for remote control.

Contoil VZD CU – Tech Data & Specs Here

Remote calculator for the VZD/VZP series. Install the VZD Control Unit in the driver cabin and you have all the necessary information about fuel consumption every time. Even competitors' flow meters from can be connected.