💡 High-Quality Power Relay Module for Raspberry Pi 4 3 2 Model B B+ A+ Review

I needed exactly 3 relays for my Pi so this was the perfect design. The only real problem is their absurd labeling, which doesn't match the Pi's pin numbers or GPIO numbers. P25, P28, and P29 are labeled on the 40-pin HAT connector, but are not the same as Pi pins 25, 28, 29, or GPIO 25, and there are no GPIOs 28 and 29 on the Pi. For those who want To use this, here are the actual pins: P25 = GPIO26, pin 37P28 = GPIO20, pin 38P29 = GPIO21, pin 40.

This product worked after I spent some time fiddling around (thanks to Jon H for providing the GPIO numbers). By default, the GPIO pins must be pulled LOW to turn the relays on and HIGH to turn them off. I've used the RPi.GPIO library with Python with no problems. I could argue that there should have been documentation BUT as there are different ways to use the Raspberry Pi (Python, Java etc) I understand why nothing was included as they differ just to explain John's review X : Relay 1 - Use…

Great addition to your Raspberry Pi. I added this hat to my Pi 3B+ to power my 3D printer. With the Pi, I can turn the printer on and off, turn on the LED backlight while printing, and turn off some fans when the printer is idle. All of this is removed. Since I don't have time to attend to the printer on long print runs, I set it up for remote access when I'm on the road. I have a live video feed to test the print and the ability to turn off ALL power to the printer in the event of a…

This board is manufactured by Waveshare. You can find a diagram and sample code on their website. The following information applies to the Raspberry Pi v2: Relay 1 - Pin 37 (marked P25 on the board) Piv2 GPIO25 Relay 2 - Pin 38 (marked P28 on the board) Piv2 GPIO28 Relay 3 - Pin 40 (marked on the board P28). P29 marked) Piv2 GPIO29* Labels on the board correspond to WiringPi code* All connections are low-active. 1=OFF 0=ON (LED also on) At boot the GPIO pins are configured via…