Calculating Fuel: Time-Based or Trip-Based

What is the difference between time-based and mileage-based calculation of fuel level?

1. Mileage-based calculation

In a standard situation, all calculations of fuel level are mileage-based. That means data from the FLS is taken only during intervals of movement (trips). Those trips are defined according to parameters set in the trip detector.

Thefts and fillings are detected if there is a difference between fuel level in following trip (X) and fuel level in previous trip (Y). If (X — Y) > 0, it is a filling; if (X — Y) < 0, it is a theft; if X = Y, it is neither. Of course, there can be some inaccuracy in data coming from the FLS. That is why, to avoid false thefts and fillings, set the following parameters on the Fuel Consumption tab of unit properties:

minimum fuel filling volume,
minimum fuel theft volume,
minimum stay timeout to detect fuel theft,
and some others.

2. Time-based calculation

This type of calculation is more complicated and is based on the following algorithm: the speed of the decrease of fuel level according to the FLS is compared with the consumption calculated mathematically. The time-based calculation is necessary for stationary units. It is also widely used for moving units for controlling thefts during the movement, for example.

Example 1.

A vehicle stayed at a parking lot during 10 hours. Defueling was made by small portions over the whole parking period. As a result, 60 liters of fuel were stolen. It is possible to determine if it was a theft o fuel consumption according to the state of the unit's ignition sensor.

Example 2.

If a device was cut off from power and a theft was done during that period, such theft can be detected by means of adjusting the maximum interval between messages.