How to Wire a Relay Switch Circuit
- 1). Turn the switch to the "Off" or "Open" position. Cut six equal-sized lengths of wire. Remove 1/2 inch of insulation from each wire end.
- 2). Solder one end of the first wire to the relay terminal labeled "85." Solder the other end of the first length of wire to one of the switch terminals.
- 3). Solder one end of the second length of wire to the relay terminal labeled "86." Attach the other end of this wire to the negative terminal on the 12-volt battery.
- 4). Solder one end of the third length of wire to the unoccupied switch terminal. Attach the other end of the third wire to the positive terminal on the 12-volt battery.
- 5). Solder one end of the fourth length of wire to one of the terminals on the light bulb receptacle. Solder one end of the fifth length of wire to the remaining terminal on the light bulb receptacle.
- 6). Solder the free end of the fourth wire to the relay terminal labeled "87." Solder one end of the sixth length of wire to the relay terminal labeled "30."
- 7). Attach the free end of the fifth wire to the negative terminal on the 24-volt battery. Attach the free end of the sixth wire to the positive terminal on the 24-volt battery.
- 8). Install the light bulb into the light bulb receptacle. Turn the switch to the "On" or "Closed" position to make the bulb light up.
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