I am trying to connect a 12V AC/DC lock to my Raspberry PI 3B+ so I can control it using python3 on the raspberry pi. Does anyone know anything I can do.

Here are my parts:

Electric lock: https://www.jaycar.com.au/12v-ac-dc-door-strike-release/p/LA5078 Relay board: https://www.jaycar.com.au/arduino-compatible-5v-relay-board/p/XC4419 Raspberry Pi 3B+

  • What have you actually done? You probably won't be able to reliably control a 5V relay module from the 3V3 Pi.
    – joan
    Jul 26, 2020 at 10:55
  • Ah, let me see. Your door lock is an "Electric Strike". You cannot control it using any relay! (1) Electric strike - Wikipedia en.wikipedia.org/wiki/Electric_strike (2) Electric Strikes - Openers-Closers openers-closers.com/source/ELECTRIC%20STRIKES_2018.pdf
    – tlfong01
    Jul 26, 2020 at 12:54
  • So It is impossible for me to control that door lock with a raspberry pi? @tlfong01
    – Aiden
    Jul 26, 2020 at 13:07
  • Ah, not at all. For us hobbyists, check out this 12V door lock catalog for those using "solenoids", not "electric strikes": aliexpress.com/w/wholesale-12v-door-lock.html.
    – tlfong01
    Jul 26, 2020 at 13:22
  • And because a 12V door lock is just a 12V solenod with a "tail". So what you need to mess around it use a 5V relay to control the solenoid (Example, ZYE-1 12V solenoid). You may find the schematic below helpful: raspberrypi.org/forums/…. Cheers.
    – tlfong01
    Jul 26, 2020 at 13:30

3 Answers 3


Aiden, the Pi is 3.3V, so on first glance the relay board may not work reliably. However the wiring should be straight forward, just do a search on raspberry pi gpio and relays.

  • 1
    any idea how to connect the relay board so I can control the lock with the raspberry pi? @dave
    – Aiden
    Jul 26, 2020 at 11:59

The 5V rating refers to the coil; 12V refers to the solenoid door lock rating.

Here's how to set up the hardware:


simulate this circuit – Schematic created using CircuitLab


Use a transistor as a switch and use 12V across that transistor. This is the safest way. Measure the relay resistance first to choose your transistor.

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