Author Topic: What is inside a magnetic lock?  (Read 1874 times)

SeanB

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What is inside a magnetic lock?
« on: December 28, 2015, 10:54:34 AM »
As I have replaced this magnetic lock with a lot more robust version, I decided to see what is inside that makes it work.

Inside there is a selector to run off either 12 or 24V DC, using 2 coils on the armature wired in either parallel or series. The lock not closed is sensed by a hall sensor that is in a slot, such that the magnetic field with an open lock does not flip the hall sensor on.

The PCB is basically there to connect to, the large TO220 device is a 7805 regulator, there to feed the hall sensor, and power the relay. The hall sensor drives both the relay and a single transistor used to drive the bicolour LED indicator, red if power is applied and the armature is not holding on the strike plate, and green if there is power and the armature is in solid contact with the strike plate. Also has a set of jumpers to select 12 or 24VDC operation.

Nice that there is a wiring diagram and jumper settings on the inside of the top cover, you do tend to lose the tiny paper slip that comes with them as original instructions. Contacts are low power, really only meant to drive a sub 100ma resistive load.

RobertoLG

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Re: What is inside a magnetic lock?
« Reply #1 on: December 28, 2015, 12:06:13 PM »
almost nothing comes with a diagram inside anymore, I did take apart an old microwave that still had the schematics glued inside, nice, thanks for sharing
« Last Edit: December 28, 2015, 12:11:05 PM by RobertoLG »