Electric Strikes

An electric strike replaces the fixed strike faceplate.  Like a fixed strike, it normally presents a ramped surface to the locking latch allowing the door to close and latch just like a fixed strike would. However, an electric strike's ramped surface can, upon command, pivot out of the way of the latch allowing the door to be pushed open (from the outside) without the latch being retracted (that is, without any operation of the knob) or while excited the knob or lever can be turned to allow egress from the secured area.

Electric strikes generally come in two basic configurations:

•  Fail-secure. Also called fail-locked or non-fail safe. The strike would remain locked in a power failure, but typically the knob can still be used to open the door from the inside for egress from the secure side.
• Fail-safe. Also called fail-open. Applying electric current to the strike will cause it to lock and if there is a power failure, the door would open merely by being pushed/pulled open.

Electric strikes are sometimes equipped with buzzers which allow someone outside the door to hear when the door is open. The buzzing noise is typically simply a result of applying AC current to the strike instead of DC, keep in mind the "buzzing" varies depending on voltage, and the coil or solenoid, although the buzzing from the AC current is audible, it is not designed to be loud for everyone to 'hear'. Using DC voltage, one would have to install an actual buzzer if they would want to "hear" the unit.