Electromagnetic locks successfully replace conventional ones for the reason that they allow you not to carry keys with you - just remember the code. They cannot be used as apartment buildings, but they can be used to protect irresponsible auxiliary premises.
Instructions
Step 1
Purchase a dedicated solenoid lock. They are available in various voltages. Also, some of them are designed for direct current supply, others for alternating current.
Step 2
To check the solenoid, apply a voltage to it with the parameters corresponding to the nameplate. Never apply DC voltage to the solenoid for AC supply. It should work with confidence every time. Do not touch the terminals of the parts even if the solenoid is low voltage, as when it is turned off, a surge in self-induction voltage is generated.
Step 3
Purchase or manufacture a power supply unit that generates voltage with the required parameters. Place it in a secure area. Use it in conjunction with an uninterruptible power supply (UPS) located there.
Step 4
Purchase a dedicated solenoid lock. They are available in various voltages. Also, some of them are designed for direct current supply, others for alternating current.
Step 5
Install the solenoid lock on the door. Drill ten holes in the door itself. Insert toggle switches with changeover contacts into them. Close them on the back with a plastic cover.
Step 6
If a DC solenoid is used, shunt it with a 1N4007 diode connected in reverse polarity. In the future, never reverse the polarity of this structure.
Step 7
Connect the toggle switches as follows. For each of those switches that must be turned on when entering the code, connect the changeover contact corresponding to the upper position with the middle contact of the next one. For each of the toggle switches, which should be off when entering the code, connect the contact corresponding to the lower position with the middle contact of the next one. Now, if at least one toggle switch is in the wrong position, the current will not flow through the circuit. With ten toggle switches, the number of code combinations can be 1,024. Change them periodically, otherwise the levers of those toggle switches that are often used will show traces by which you can distinguish them from the rest.
Step 8
Turn on in series the solenoid, the chain of toggle switches and the bell button installed in front of the door. Connect this circuit to the power supply (observe polarity if using a DC solenoid). Insulate all connections carefully.
Step 9
To enter the code, set all the toggle switches to the correct position, and then press the bell button. Open the door, release the button, and then set all toggle switches to the off position.
