Commercial Door Refusing to Close — Safety Sensor Repair in Carrara

A Carrara business called because their commercial door would not close reliably. It would start to come down, then reverse back up — sometimes on the third or fourth attempt it would close, other times staff gave up and had to stand by the door pressing the wall button. With the door unable to be trusted to close, the premises could not be secured at the end of the day.

The behaviour — door opens fine, refuses to stay closed — pointed straight at the photoelectric safety sensors, so that is where I started. One sensor had been knocked out of alignment on its bracket, and the wiring connection at the same sensor was faulty, so the beam was dropping out intermittently. Every time the beam broke, the opener treated it as an obstruction under the door and reversed. Nothing was wrong with the motor or the door itself.