Miswired switches

nizak

Senior Member
Had a customer call about existing interior switching not working properly.

It’s a business with a large open space and a total of 7 switches ( located a various entrance and exit points of the room)

Haven’t been there but would assume 2- 3 ways and 5- 4 ways.

Sounds like mis wired switches.
She said up till now she hasn’t been able to sync them where she can operate them all effectively.

Just start opening boxes and look for the correct pairing of travelers??

Any other way to approach it?
 
First, find out if they ever worked, or never worked.

Then, start at the 3-ways, identify incoming power, feed to the lights, and then travelers.

If power is ran to the fixture first, then switch leg down to the first 3-way, it can get a little complicated. Ugly’s has a nice diagram of proper wiring for that scenario.
 
I have found that 4-ways fail more often than 3-ways. I would start with were they ever working right, as was mentioned. Then operate them yourself. You know the power and load leg to light works if the lights come on in certain switch positions. Then it's just a matter of opening boxes. You could either use your meter to check each switch, or bypass a switch by tying the conductors together. You could tie all the 4-ways straight through, one at a time, to verify the 3-ways work. If they do, then you know it's one of the 4-ways that is bad.

It could also be that the switches were never wired correctly to start with. Maybe a certain switch was used all the time and others not used. Then someone tried other switches and discovered they weren't working. Then you would have to see which one is wired wrong.
 
I have found that 4-ways fail more often than 3-ways. I would start with were they ever working right, as was mentioned. Then operate them yourself. You know the power and load leg to light works if the lights come on in certain switch positions. Then it's just a matter of opening boxes. ...

Perhaps before opening boxes, you could use a non-contact voltage tester to help narrow down the problem as follows:

If you can get the switches in positions where the lights are turned on, first verify that you can get the tester to light up near each switch handle. Preferably, you would lower the sensitivity on the tester so that it only triggers when you are very close to the switch itself.
Then you could go to each switch one at a time, flip it so the lights are off, and then check if the other switches still trigger the tester. If the 4-ways are good without a bad contact, one of their two traveler outputs should still be hot. If not, then that 4-way would be bad and the downstream switches would not have any voltage. Therefore the tester should not trigger on them.

There is the limitation that other wiring in a switch box may remain hot and still trigger the tester, even though the 4-way (or the 3-way to the load) being tested has no voltage because of a bad upstream switch. But if any other switches stop triggering the tester when a switch is flipped, there's a good chance that flipped switch has an open contact.
 
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There is the limitation that other wiring in a switch box may remain hot and still trigger the tester, even though the 4-way (or the 3-way to the load) being tested has no voltage because of a bad upstream switch. But if any other switches stop triggering the tester when a switch is flipped, there's a good chance that flipped switch has an open contact.
I'm not aware of any non-contact testers where you can adjust the sensitivity. Not saying they don't exist, just that I never seen one. You are correct in that other wires near the ones you're testing are very apt to trigger the tester.
 
I'm not aware of any non-contact testers where you can adjust the sensitivity. Not saying they don't exist, just that I never seen one. You are correct in that other wires near the ones you're testing are very apt to trigger the tester.

Here's one with a sensitivity adjustment:

 
If they worked correctly before, possible failed three way, but if never worked, yes, probably traveler miswire.
Per the owner it doesn’t appear they ever worked correctly from original build 2 years ago.

From looking at some of the other work this EC did I doubt they ever sequenced all the switches to ensure proper operation.



She did tell me that the EC has been contacted on various issues but wont come back to address them.
 
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