Now that we know how a relay works, it's relatively easy to connect our lamp to it. Since we want the lamp to be illuminated when we turn the relay on (set D1to HIGH), we will use the NO and COM connectors, and let the NC connector be. If the lamp has a normal two-wire AC cable, we can insert the relay into the AC circuit by simply cutting one of the wires, inserting one end into the NO connector and the other into the COM connector, as is illustrated in the following figure:
Connecting a lamp
Be sure to follow appropriate safety regulations when working with electricity.
