Basic principle of overrun detection: the tested vehicle first passes through the pre inspection system, and the system load cell will pre inspect the vehicle axle load and vehicle passing state and transmit it to the data collector. The data collector will analyze and process the above information to form a complete vehicle information. It includes: detecting the axle weight of the vehicle, the cumulative total weight of the vehicle, the passing speed of the vehicle, the wheelbase of the vehicle, the vehicle model and whether the vehicle passes. When the detected vehicle passes completely, the system transmits the collected vehicle information to the control host in real time. The control host receives the data of the license plate recognition system and matches the weight information to form a complete vehicle information, which is stored locally and uploaded at the same time. The communication machine judges whether the vehicle exceeds the limit according to the axle load and total weight limit entered in advance. Once it is found that there is a suspicion of exceeding the limit, it will prompt the suspected vehicle.​