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Original post: Need help! Single pole switch with 3 black wires
Need help! Single pole switch with 3 black wires
I replace my single pole light switch and noticed when I removed the old switch that three black wires come from the box. All white lines are interconnected and the same goes for the ground lines. Of the three black lines, only one of them is hot. The old switch is secured with two black inserts on the back of the switch with a further black attachment to the screw. I'm confused about how to switch the switch again. I forgot to write down which wire went there when I removed the old switch so it's my own fault. Any help would be greatly appreciated.
Nashkat1 – Member
Welcome to the Forum!
"The old switch is attached with two black inserts on the back of it switch with another black attached to the screw. I am confused about how to switch the switch."
One of the two non-hot black wires is the light feed and the other is a feed to other loads – possibly some containers, but it doesn't matter.
Connect the black hot wire to the old switch when it is turned off. Connect one of the other two black wires to the other screw on the switch. Turn on the power again and turn on the power switch. The light either lights up or not.
If the lamp comes on, the other black wire you connected to the switch is the power supply and the unconnected black wire is the feed to the other loads. If the light is not lit, it is the opposite: the connected wire feeds the other loads and the disconnected wire is the light supply.
Turn off the power and select the wires before disconnecting them. End the light supply to one of the two screws on the new switch. Do not use backstabs, even if the new switch has them. Splice the hot thread, feed for the other loads and a short black pigtail together. Cut and attract the joint. Connect the pigtail to the other screw on the new switch.
cbailey22 – Thread Starter
Thanks Nashkat1, who worked.
Nashkat1 – Member
Glad you got it resolved, and thanks for the feedback.