Scan our QR code for more exciting content from ICD!

Commonly used locks in electronic security solutions part 1: Electromagnetic locks

In the first part of this series, we introduce electromagnetic locks and how they should be used in your security system

Electromagnetic locks, commonly referred to as a Maglocks, consist of an electromagnet and an armature plate. The principle behind an electromagnetic lock is the use of electromagnetism to lock a door when energized. The holding force should be proportional to the load, and the lock and armature plate should be face-to-face to achieve optimal operation.

The magnetic lock is suitable for both in-swing and out-swing doors. Brackets (L bracket, LZ bracket, U bracket) are used to adjust the space between the door and lock.

The magnetic lock should always be installed on the inside (secure side) of the door. Most installations are surface mounted. For safety, magnetic lock, cables, and wires should be inserted in the door or be a flush mount.

There are two main categories of maglock, namely "fail safe" and "fail secure". By attaching the electromagnet to the door frame and the armature plate to the door, a current passing through the electromagnet attracts ("fail safe") or releases ("fail secure") the armature plate

A magnetic lock has a metal plate surrounded by a coil of wire that can be magnetized. The number of coils determines the holding force of the lock:

 

  • Micro Size: 300 lbs (1,300 N) holding force.
  • Mini Size: 600 lbs (2,700 N) holding force
  • Midi Size: 800 lbs (3,600 N) holding force
  • Standard Size: 1,200 lbs (5,300 N) holding force.

 

 

The standard size electromagnetic lock is used as a gate lock.

Electrical Requirements : The power for an electromagnet lock is DC (Direct Current), around 6 W. The current is around 0.5 A when the power is 12 V DC. Generally, the specification of the electromagnet locks is dual voltage: 12/24 V DC. Single voltage output can be configured for 12 V DC or 24 V DC applications. When the current is fixed, voltage is proportional to power consumption.

Power supplies incorporating a trickle-charged lead-acid battery pack can be used to retain security for short-term power outages.

 

Advantages:

 

  • Easy to install: Magnetic locks are generally easier to install than other locks since there are no interconnecting parts.
  • Quick to operate: Magnetic locks unlock instantly when the power is cut, allowing for quick release in comparison to other locks.
  • Sturdy : Magnetic locks may also suffer less damage from multiple blows than do conventional locks. If a magnetic lock is forced open with a crowbar, it will often do little or no damage to the door or lock.

 

Disadvantages:

 

  • Requires a power source in order to be secure
  • Can be disconnected in the event of a power outage disabling security