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Discussion Starter · #1 ·
No wirenut, no tape, just bare neutrals. :no:

Has this ever been done by a pro?

This is original wiring, I'm sure, as all the wires are soldered. Apparently, since there's no ground (and the metal box isn't grounded) the installers never considered this a problem?!?

Is it a problem, considering the neutrals were pushed in the back and away from any possibility of coming into contact with the switch terminals?
 

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Although it looks like they were soldered, they should have been insulated. If they touched the metal box they could have put current onto parts that should not be energized.
 

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Discussion Starter · #5 ·
This switch goes to a ceiling fan/light that has gone out. Why wouldn't there be 120v between the black and red with the switch removed? Every switch I've measured had 120 between the switch leads with the switch out.
 

· I=E/R
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This switch goes to a ceiling fan/light that has gone out. Why wouldn't there be 120v between the black and red with the switch removed? Every switch I've measured had 120 between the switch leads with the switch out.
You would have to have a complete circuit through the fixture to pick up the neutral. Why anyone would try and measure voltage that way in a switch circuit is beyond me.
 

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Discussion Starter · #7 ·
Why anyone would try and measure voltage that way in a switch circuit is beyond me.
Well, I just took the fan down from the ceiling, and found that the neutral had come loose. So, I ran a new pigtail, and all works fine. I wonder if there would be 120v between the disconnected switch wires now, and if so WHY? :huh:

Maybe I've stumbled upon a troubleshooting technique? If you don't find 120v between the switch wires (when d/c from the switch), then you know there's a failed neutral?

I don't know, it's just that in the past, when I've disconnected switches, and measured voltage between the two switch wires, I've always read 120v, and I've never undertood why. It seems like all I'm doing is measuring a wire because 2 wires on a switch simply completes the hot leg to the light. ??
 

· I=E/R
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AC Power => Switch => Load => Neutral
AC Power => Meter => Load => Neutral

Let's assume the Load is 12 ohms and the power 120 V. I=E/R
The switch has a theoretical resistance of 0 ohms so with the switch closed there will be 10 amps flowing.
A digital meter has a 10 meg ohm input resistance so now the circuit resistance is 10,000,012 ohms and the current flow is .000012 amps - that is 12 microamps which isn't much load.
If a motor or other device is failing, you should be troubleshooting at the point of failure so you have access to both current carrying wires. Troubleshooting at a switch in house wiring can be tricky because you don't always have a neutral and in older wiring you may not have a ground either.
 

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I was looking at the photo let me clear up couple details for ya real quick.,

The splices were done in " old school " methold which it was solidering I know it was common before late 1960's after that everything went with wirenut.

Now that switch box you have there you do have actual neutal there and the three conductor you have there on right side of the switch which I am pretty sure that is that for the ceiling box where you are working the white is netural of course and the black is UNSWITCHED conductor which it mean alive all the time and red is switched { control by switch } so when you get back to that box kill the breaker or remove the fusé when you work on the ceiling box.

That how you are reading full 120 volts due the black conductor is unswitched and if you have digtial meter they are very senstive to ghost or inducted voltage so get a neon test light they will verify if that is actually engerized or not.

Merci,
Marc
 
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Discussion Starter · #10 ·
Thanks a7 & Marc. I am aware of Phantom Voltages, so whenever I get less than 100v I know it's not right. Plus, I use a Wiggy for voltage measurements.

a7, it's so obvious that troubleshooting should begin at the fan. Sometimes I just need a hit on the head ;)

Also, thanks for reminding me that the meter is closing the circuit!
 
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