We determine the minimum number of sensors with the expectation that at least one sensor must be placed on each general axis. The exception is the "tractor + semitrailer" configuration, where no sensor is placed on the front axle. In this case, the load on the front axle is determined based on the load on the tractor's rear axle, the position of the fifth wheel coupling and the distance between the front and rear axles of the tractor.
So, for the configuration of a 3-axle tractor and a 2-axle semitrailer, the minimum number of sensors required for installation is 2 pcs. For a 2-axle truck with a 3-axle trailer, the minimum number of sensors for the installation is 4 pcs. For a 3-axle truck, you can limit yourself to 2 sensors.
The minimum number of sensors in the weighing system and the control of the axle load imposes a number of limitations related to the operation of the system. First, the weight of the load and the load along the axes will be correctly displayed if the load in the body is positioned so that its center of gravity is in the middle between the right side of the side of the body and the left. Secondly, in the case of lifting axles, the load on the axle and the weight of the load when one of the axles is raised will not be displayed correctly.
Determine the number of lifting axles. Each lifting axle is equipped with at least one sensor. One sensor against two sensors imposes a certain restriction, namely, the position of the center of gravity of the load should be in the middle from the right edge to the left edge of the vehicle.
Since the center of gravity of the load (most often) is not located in the middle with respect to the right and left sides of the vehicle, it is recommended to put two sensors per axle. The exception is the rear axle of the tractor, here, setting the sensors on each side is not very important, because the condition of the center of gravity is fulfilled (the fifth wheel is located in the middle) relative to the right and left sides of the tractor. Also, just one sensor is sufficient, if in the air suspension the right pillow and the left have a common line, then there is no sense in placing two sensors on each side.
So, the optimal version of the number of sensors for the configuration of a 3-axle tractor + 3-axle semitrailer with the 1st lifting axle is 5 pcs.