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Raspberry Pi 4b, PSU control installed, relay does not work.

Problem: Raspberry Pi 4b, PSU control installed, relay does not work.

  1. For relay, connect the power cord brown wire to NO, COM.
  2. Relay IN is assigned to GPIO 17 and connected.
  3. If you give a signal to number 17 from the terminal, it works properly. The relay clicks and the power is turned on/off
  4. After installing and setting the Psu plugin, the relay does not work when clicking the Psu icon at the top.

Make sure you didn't mix up pin and gpio number

The gpio pin connection seems to be correct. After all, when I connect the 5V relay to the 3.3V voltage, it works! What could be the cause?
When measuring the 5v of the Raspberry Pi board with the tester, it seems that about 4.0v and 3.3v are about 2v output.

Could be a bad tester / bad tester cables
Pretty sure that the pi would brown out at 4V.

just tested it myself and it works fine for me

But I noticed 2 things.

  1. Why are you using 3 completely different colored jumper cables in both pictures
  2. Why isn't there a connection to GND?

The reason the color of the wires is different is that I connected two wires by soldering them in succession. It is connected to gnd.
The problem is that the 5V relay doesn't work for 5V and I don't know if it works for 3.3V.
Let's test it with another new tester ....I will also change to a genuine Raspberry Pi adapter.

My bad - it was late and I miscounted.. Thought it was on GPIO 17 and GPIO 27

ok thanks

I measured the 5V power pin again with another tester. It comes out to about 5.2V. It seems that the tester was broken before. ^^

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