Commercial Door Operator Safety Systems - DDM Garage Doors Blog

Posted August 21st, 2020 at 5:53 pm by Dan Musick

Commercial door operator manufacturers have designed three standard safety systems.

First is the mechanical clutch that slips when the door is obstructed.

An image of the interior of a LiftMaster commercial door operator.
A spring-loaded pulley, pressure plate, and disc stop the travel of the operator if the door is obstructed.

The second design is the eye sensor system. If a vehicle or a person passes under the door and blocks the eyes, the door operator will reverse the door until it raises to the open position.

A view of safety eyes installed on a Commercial Door Operator as part of the safety system.
Safety eyes prevent the door from injuring people and damaging vehicles that might be under the door as it closes.

The third safety system for commercial door operators is the internal electromechanical sensor or an electrical sensor. These can detect changes in motor speed. If there is an obstruction such as a locked door, a broken spring or a broken cable, the motor speed will slow and stop the door if it is opening. Otherwise, the motor will stop the door and cause it to open if the obstruction occurs as the door closes.

A closure view of RPM sensor in a LiftMaster commercial door operator.
A plastic wheel with “windows” rotates through the infrared RPM sensor and counts the motor revolutions to stop and reverse the operator travel.

More information is on our YouTube video by the same name.

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