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Discussion Starter · #1 ·
I'm at a complete loss to understand what at all is going on here:

The original complaint was a hall light (controlled by two three ways )not working. I tested at the fixture, found 17 volts, switched to low impedance and got it down to 0. OK, so no power to fixture.
Opening both switch boxes, I found an incoming cable, also an outgoing cable(on to a bathroom), and the wiring between the two switches and to the light.
Testing the three power conductors (incoming,outgoing and to switches) while still twisted together also resulted in 17V to ground and 0V using low impedance.
I then disconnected these three wires apart, the bathroom light shut off! I tested each wire separately, found 117V in incoming power which went down to 0v with low impedance! The outgoing to bathroom was giving 80V and also 0v with low impedance.
Not sure what to do I reconnected the wires, sure enough the Bathroom light went back on. I clamped it, and got appropriate current for the bathroom load.
Basically there's ghost voltage everywhere, the hall light does not have the power it needs, and the bathroom lights seem like their running on nothing.
And no it's not as simple as the black conductors actually being the neutral, first of all there would not be any ghost voltage, and secondly I think it would all still work fine if that was the case.
Maybe I'm missing something here but I just have no idea what's going on.
 

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I'm at a complete loss to understand what at all is going on here:

The original complaint was a hall light (controlled by two three ways )not working. I tested at the fixture, found 17 volts, switched to low impedance and got it down to 0. OK, so no power to fixture.
Opening both switch boxes, I found an incoming cable, also an outgoing cable(on to a bathroom), and the wiring between the two switches and to the light.
Testing the three power conductors (incoming,outgoing and to switches) while still twisted together also resulted in 17V to ground and 0V using low impedance.
I then disconnected these three wires apart, the bathroom light shut off! I tested each wire separately, found 117V in incoming power which went down to 0v with low impedance! The outgoing to bathroom was giving 80V and also 0v with low impedance.
Not sure what to do I reconnected the wires, sure enough the Bathroom light went back on. I clamped it, and got appropriate current for the bathroom load.
Basically there's ghost voltage everywhere, the hall light does not have the power it needs, and the bathroom lights seem like their running on nothing.
And no it's not as simple as the black conductors actually being the neutral, first of all there would not be any ghost voltage, and secondly I think it would all still work fine if that was the case.
Maybe I'm missing something here but I just have no idea what's going on.
You keep saying you checked from (something) to ground. Have you checked to neutral? Where does the power come in, the light or the switch?

Run an extension cord from a known working receptacle and check your wires to neutral. You should be able to find the power feed and get a better reading than by checking to ground. Especially if you're unsure which is the neutral.

If you're only checking to ground, the bonding may not be good and you won't get an accurate reading.
 

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THE "BIG RED MACHINE"
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you have burnt connections in their device boxes , tell the customer it's better to have a comprehensive inspection of all the device boxes cuz they got problems in that house.
if the customer doesn't want to spend the money to look at all the device boxes, write up a ticket and a billl, shut the power off and tell them that their electrical system is not safe.
 

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THE "BIG RED MACHINE"
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show your customer the difference between a nice commercial grade device, and the crappy devices they have in their house. tell them that you can make them saved by changing out all the devices and check on the panel, tell him how you're going to torque everything down and tighten ,everything make it secure and safe with the device upgrades. charge and 1500 bucks or so, this tiny $150 repair jobs aren't going to make any money, I've been offering device upgrades for years now you don't get them all but it's better that way.
 

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show your customer the difference between a nice commercial grade device, and the crappy devices they have in their house. tell them that you can make them saved by changing out all the devices and check on the panel, tell him how you're going to torque everything down and tighten ,everything make it secure and safe with the device upgrades. charge and 1500 bucks or so, this tiny $150 repair jobs aren't going to make any money, I've been offering device upgrades for years now you don't get them all but it's better that way.
You work for Mr. Sparky?:whistling2:
 

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Get a solenoid tester like a wiggy. Your digital multimeter is confusing you and you are chasing ghosts. Use an extension cord to make sure you have a solid neutral at the light fixture, and go from there. You know the circuit from the source is good as the bathroom is working, so the problem lies from that switchbox, to the next one, to the light.
 

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Discussion Starter · #10 ·
Okay looks like I'm not missing anything simple , I'm just gonna start opening up more boxes and trace the circuit to the panel. And I'll use an extension cord to test for voltage. Definitely something funny going on.
 

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THE "BIG RED MACHINE"
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Okay looks like I'm not missing anything simple , I'm just gonna start opening up more boxes and trace the circuit to the panel. And I'll use an extension cord to test for voltage. Definitely something funny going on.
don't forget to check your lighting fixture box is also, hope you can make some money.
 

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If 120v is there then there is no need to follow anything back to the panel. Make sure you have 120 neutral to hot, then wire it up! Probally a crappy device or loose connection
 

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Is it wired with knob and tube, if so it sounds like a blown fuse on the neutral.
Probably located in the attic or a closet.
 

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Discussion Starter · #15 ·
Whoa, knob and tube fuses the neutral? Why?
Either way that's probably the issue, the house doesn't look older than 30-40 years.
 

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This is where I would toss the meter, and not frustrate myself any further.

Get an old porcelain light socket, or even a desk lamp and two alligator clips.

Hook one side to a good neutral and go to it finding where the voltage starts and ends. That light bulb wont lie to you (unless its burned out:laughing:)
 

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You keep saying you checked from (something) to ground. Have you checked to neutral? Where does the power come in, the light or the switch?

Run an extension cord from a known working receptacle and check your wires to neutral. You should be able to find the power feed and get a better reading than by checking to ground. Especially if you're unsure which is the neutral.

If you're only checking to ground, the bonding may not be good and you won't get an accurate reading.
Get a solenoid tester like a wiggy. Your digital multimeter is confusing you and you are chasing ghosts. Use an extension cord to make sure you have a solid neutral at the light fixture, and go from there. You know the circuit from the source is good as the bathroom is working, so the problem lies from that switchbox, to the next one, to the light.
I must have not said that loud enough, or spelled something funny!:):whistling2::jester:
 

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neutral, :thumbsup:
 
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