Use magnetic or electronic keys to open the electromagnetic lock.
One of the features of these locks is the need for continuous supply of current to the coil of its electromagnet. In the event of an accident the power supply of the electromagnetic lock opens. Just unplug the power and lock rasplachivaetsya, the door will open. This feature of the castle played an important role in ensuring fire safety.
Electromagnetic locks have relatively high mechanical load on the margin, the so-called holding force of the door. The holding force of the door is measured in kilograms and depends on the model of locks. There are models for 100, 150, 200, 300, 400, 500 pounds.Make an effort equal to the holding force of the door and maybe the door with the electromagnetic lock will open.