- Nov 27, 2019
- Reaction score
- Ålesund, Norway
Thanks for the input.Relay boards have naked opto-coupled inputs and will not do anything more than provide a small input load on the NodeMCU IO.
Some boards support 3.3V signalling reliably while providing a 5V input to the relay coils, you have to run separate power leads to the board for that configuration (which is probably what you want to do)...
My relay module has Vcc, In1,In2 and GND for the optocouplers, I guess this should be 3v3 (this is where I screwed up and put 5v).
For the coils it has a JDvcc, Vcc and GND. To make them work with the jumper between JDvcc and Vcc, you need to put 5V on the opto coupler Vcc, so I have removed the Jumper and put 5V on JDvcc. The two GND pins are connected together, so I don't see any reason to use both.
I believe this is the correct way to do it on a 3v3 chip?