Door holder electro magnets fire door control
The magnetic doorholder consist of an electromagnet with steady current and an armature. Its task is to keep the door or shutter in open position as long as the current is on. By disconnecting for a moment the current, the magnet will release its grip and the door resp. shutter is closed by means of normal doorclosers, counter weights, sliding plane or similar. The doorholder can be equipped with different types of mechanical fixing devices. These fittings allow an adaption of magnets and armatures to different types of doors and shutters.
Impulse devices can consist of heat detectors, smoke detectors, flame detectors, sprinkler centrals or manual alarm pushbuttons. These devices can be incorporated in a fire alarm system or be separately arranged for only door control.