If the force plate was working, but stopped, the most common cause is that the Force Plate was damaged by being subjected to too much force. This can happen when students try to jump on it as hard as they can, which causes the internal load cell to buckle and fail.

When this happens, the electrical output of the Force Plate is pinned at either 0V or 5V, causing the reading to be stuck either at -1000 N or 4000 N (in the 3500 N range setting) or -250 N or +1000 (in the 850 N range setting).

The Force Plate must be returned to Vernier for repair.