Should an ANPR camera be mounted in the front or the back?

When installing an ANPR camera, we are often asked what the ideal distance from a barrier is and whether the camera should be placed in front of or behind the barrier. However, there is no hard-and-fast rule. The correct position depends on one key question: should the license plate be read while the vehicle is stationary or while it is moving?

Stationary

Does a driver first have to stop at a registration kiosk? In that case, the license plate is best read when the vehicle is stationary. That’s why we often use a presence loop that activates license plate recognition only once the vehicle is correctly positioned.

This approach is also used in FastFlow systems, where, for example, payment begins the moment the license plate is registered.

While Driving

Not every application requires a vehicle to stop. In systems where vehicles are allowed to drive through automatically, the camera can be positioned in front of the barrier. The license plate is then read as the vehicle approaches, allowing the system to respond more quickly and maintaining maximum traffic flow.

By tailoring the placement to the application’s operation, you increase both the recognition rate and ease of use for drivers.