A magnetic lock is a simple locking device that consists of an electromagnet and armature plate.
By attaching the electromagnet to the door frame and the armature plate to the door,
a current passing through the electromagnet attracts the armature plate holding the door shut
Unlike an electric strike a magnetic lock has no interconnecting parts and is therefore not suitable for high security applications
because it is possible to bypass the lockby disrupting the power supply.
Nevertheless, the strength of today's magnetic locks compare well with conventional door locks and cost les
than conventional light bulbs to operate.Operation: The magnetic lock relies upon some of the basic concepts of electromagnetism.
Essentially it consists of an electromagnet attracting a conductor with a force sufficiently large enough to prevent the door from being opened.
In more detailed examination,the device makes use of the fact that
a current flowing through one or more loops of wire (known as a solenoid) produces a magnetic field.
This works in free space, but if the solenoid is wrapped around a ferromagnetic core such as soft iron the effect of the field is greatly amplified.
This is because the internal magnetic domains of the material align with each other to greatly enhance the magnetic flux density.
Technical comparison: Magnetic locks possess a number of advantages over conventional locks and electric strikes.
For example, their durability and quick operation can make them valuable in a high-
traffic office environment where electronic authentication is necessary.
Nevertheless in a number of applications economic or security reasons can lead to conventional locks
or electric strikes being a better choice.
Advantages: Easy to install: Magnetic locks are generally easier to install than other locks given there are no interconnecting parts.
Quick operation: Magnetic locks unlock instantly when the power is cut allowing for quick operation in comparison to other locks.
Durable: The lack of interconnecting parts means the lock is far more durable than other locks especially when used in high traffic areas
Installation: The magnetic lock is generally placed on the inside of the door frame to prevent tampering.
It is important to make sure the armature plate and the electromagnet align as closely as possible to ensure efficient operation.
Magnetic locks are almost always part of a complete electronic security system.
Such a system may simply consist of an attached keycard reader or may be more complex involving connection to a central computer that monitors the building's security.
Whatever the choice of locking system, fire safety is an important consideration.
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