4 switch combination Combination Lock

Posted on Dec 13, 2012

This circuit is very basic to build. To open a lock which is connected to the K1 Load, you must press each momentary switch in the correct sequence. The sequence used in this circuit is S1, S2, S3 and finally S4. If any of the other switches are pressed the circuit will be reset and you will need to start over.

4 switch combination Combination Lock
Click here to download the full size of the above Circuit.

Depending on how you wire the switches, you can use any 4-switch combination.

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