FSH Magnetic Door Holders
Door Hold Open Magnets are electro magnetic devices to hold fire and smoke doors in an open position. On a principal similar to Electro Magnetic Locks they consist of a round electromagnet (constructed of carbon free steel-core, surrounded with hundreds of turns of copper wire) and a round armature plate (steel plate). Door Hold Open Magnets can be wall or floor mounted and are connected to a smoke and/or fire alarm system. The device releases the door from the hold open position when fire/smoke alarm or manual release button is activated.