ELCO offers a wide range of safety  locks and safety  switches for control doors, sliding doors and other protective devices that protect the machine from inertia. Safety door locks include mechanical lock M and electromagnetic lock E two series. Working principle of mechanical lock: insert latch lock when power is off, release and remove latch after power is on. Working principle of the electromagnetic lock: insert the latch and lock in the state of power, release and pull out the latch after power off.