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Electric Locking Systems

An electric lock is possibly the most important part of your door entry system. The lock is linked to your door entry device and on activation will release the door so that the person trying to gain entry can pass through the door. Regardless of how much effort you put into having the correct door entry product to protect your door it will be let down if a poorly specified electric lock is installed into the door.

When choosing electric locking, there are 2 variants available. Fail Locked and Fail Unlocked -

Fail Locked - When the electric lock has no power to it the door is locked, power is then applied to release the door. Generally with a fail locked electric lock the inside of the door would have some form of lever to exit the door.

Fail Unlocked - When the electric lock has no power to it the door is open, power is then applied to the to lock the the door. Generally, a fail unlocked device is used in conjunction with a fire alarm system and the door would have either a lever or an exit button/break glass unit to exit the door.

SLS can give expert advice as to the types of locking available and listed below are common forms of locks along with their applications -

	Rim Releases A rim release is used in conjunction with a rim lock (i.e. Yale nightlatch) and is commonly used on audio and video door entry systems. The electrically operated release allows the door latch to open freely when activated and when the door closes, preferably using a door closer, the latch springs back into the jaw of the locked electric release. These releases are available as fail locked or fail unlocked and a number of finishes are available including brass, chrome, grey and other polished finishes on request.
	Mortise Releases A mortise release is used in conjunction with a mortise lock (i.e. Union mortise nightlatch) and is commonly used on both audio and video entry systems and access control systems. The electrically operated release allows the door latch to open freely when activated and when the door closes, preferably using a door closer, the latch springs back into the jaw of the locked electric release. These releases are available as fail locked or fail unlocked and a number of finishes are available including brass, chrome, grey and other polished finishes on request.
	Electromagnets Electromagnets are an all-in-one device used on doors instead of a conventional lock and electric strike. The magnet is fixed to the frame at the top of the door and an armature (locking) plate is fixed to the door. When the magnet is energised it creates a strong magnetic bond between the magnet and its plate, roughly between 300-600 KGs, and this holds the door secure. The moment the power is taken off the electromagnet it instantly releases the door. This method of door locking makes this type of lock ideal for a fire alarm integration as when the fire alarm is activated it sends a signal to drop the power to the lock and the door is free to exit. Due to their nature of operation, electromagnets are only available as a fail unlocked device. They are available in various finishes (RAL and BS coatings) and also in plain or anodised full door width housings.
	Electromagnetic Shearlock This type of locking works in the same way as a standard electromagnet in the fact that a strong magnetic magnetic bond is created when the lock is energised, roughly 1500 KGs, but this lock differs as it can be used on double action sets of doors. The magnet and armature are fitted completely flush into the door an frame and the door is free to swing. When the lock is energised a sensor within the magnet body senses the magnet and armature coming into alignment. The armature plate is on a sprung housing and as the magnetic force is created it is pulled up to the magnet. The magnet body has locking pins which locate into holes on the armature body and this creates the shear force that hold the door locked. Due to their nature of operation, electromagnets are only available as a fail unlocked device. They can be flush or surface mounted and they are available in various finishes (RAL and BS coatings) and also in plain or anodised full door width housings.
	Solenoid Bolt This is another type of lock suitable for double action doors. Instead of a magnetic force, this lock has a shoot bolt that strikes into the strike plate when the door is in alignment. As these locks are not driven by a magnetic force, they are available as both fail locked and fail unlocked. Solenoid bolts can be surface or flush mounted and their surface housing's are available in a number of different finishes including brass, gold and chrome plated.