Magnetic locks are devices that secure door or gate entryways by using magnetic force. Current is supplied to engage the electromagnets in a hold or cut-off position, allowing the door or gate to be opened. These devices are used in commercial applications as well as industry.
Magnetic locks are almost always electromagnetic and are used to lock doors typically for lower security due to the fact that they need power to operate. The magnets have different holding forces depending on the specs and require different voltages and currents to operate. Some magnetic locks have holding forces equal to traditional mechanical locks.
Composition and Operation
Magnetic locks generally consists of two parts: an electromagnet and an armature. The armature (a metal plate made of steel or another ferrous metal) is usually mounted to the door while the electromagnet is mounted to the door frame. When power is applied to the magnet, it will attract the metal plate and hold the door shut. When the power is turned off, the door can be opened.
Locks can be different shapes, including round, square, rectangular, and various sizes. Typically, the larger the size the stronger the holding force. They can operate on AC or DC depending on what they are designed for and have varying efficiencies based on the amount of power consumed. Some locks have battery backup systems to keep them locked for a period of time in the event of a power outage.
There are a number of specifications to consider when selecting magnetic locks.
Magnet size is the size of the electromagnet piece of the lock. A correctly sized magnet will fit the door it is being installed on.
Armature size is the size of the metal plate piece of the lock. A correctly sized armature will fit he door it is being installed on.
Holding force is the amount of force the magnet supplies to hold the door in locked position. Locks with higher holding force will be more secure and more difficult to break open.
Voltage and current ratings determine the operating voltage and current requirements for the lock, given in volts and amps (respectively).