Hardware – Relays

I have found these common relay modules to be suitable for the control outputs for the home hub, where switching of mains voltages is required. They feature optical isolation, are low cost, come in single, dual and multiple packages and are readily available from a number of suppliers. There are many tutorials on the web if you require further information on interfacing, but do take care when working with mains electricity, and consult a qualified electrician if in any doubt.