Getting Started With The Raspberry Pi Relay HAT
Our Pi Relay HATs are designed to allow your Pi to switch higher voltages and higher currents from one self contained board. In this tutorial we are going to go over soldering the header to the Relay HAT, use Python with the included Pi.GPIO library to write code that triggers each relay, and go over the external relay connections and configuration options on the board. This tutorial can be used for both the 4 Channel Standard Relay HAT and the 2 Channel Pi Zero Relay HAT.
About The Boards:
We make two versions of this relay board, one for the standard Raspberry Pi with 4 relays, and one for the Raspberry Pi Zero with 2 relays. On the board, each relay’s Common, Normally Open, and Normally Closed pins are brought out to screw terminals. These are not the most sophisticated circuits, but they do provide a compact, permanent solution for attaching a number of relays to the Pi.
If you have any questions, or need further clarification please post in the comments section below; this way future users of this tutorial can see the questions and answers!