Monarch NICE900 Door Operator Fault: Er31 – Door Opening Obstruction Protection

Symptom: The door stops halfway during the opening process, displays error code Er31, and repeatedly stalls/stops.
Comprehensive troubleshooting steps:
Visual inspection of the track: Check the opening-side guide rail, door sill, and gaps between door panels for pebbles, debris, or deformed components obstructing the door.
Check torque parameters: Access the torque settings; if the upper limit for opening torque is set too low, even slight resistance triggers the protection mechanism-increase the torque limit appropriately.
Adjust obstruction detection timing: If the detection time for opening obstructions is too short, the system stops upon encountering minor resistance-extend the detection duration.
After clearing obstructions and adjusting parameters, power-cycle the door operator to automatically reset the fault.