voltage on "traveler" on a 3 way circuit

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sparkync

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Where does the voltage come from on the "traveller" not being used on a 3 way light circuit? When 3 way light is switched in one position, it throws 120 volts to the "switch leg" to the light from one of the "travelers". With my tester on the other traveler" I can get around 50 volts or more. Why is this happening?
Thanks
 
sparkync said:
Where does the voltage come from on the "traveller" not being used on a 3 way light circuit? When 3 way light is switched in one position, it throws 120 volts to the "switch leg" to the light from one of the "travelers". With my tester on the other traveler" I can get around 50 volts or more. Why is this happening?
Thanks
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Induced voltage on the floating wire, which is physically close-coupled in the cable, placing the voltage somewhere between that of the hot and grounded wires nearby.

If you used a low-impedance tester like a solenoid tester, or a small light bulb in parallel with your high-impedance voltmeter, the induced voltage would collapse to zero.
 
It's generally called ghost voltage.
In layman's terms, when a hot wire is laying next to another wire that's not hot at the moment, the "not hot" wire is laying in the magnetic field of the hot wire and tricking your digital volt meter into thinking there's some voltage there
 
But also, if you turn the light off at the load end, that switch breaks connection with a live traveler and goes to the dead one. So you do have real live voltage there but it stops at the switch.
 
The customer I had also had an "equipment ground" wire that was attached to the yoke of his switch. He had it taped black just to insulate it.
He was having problems with the 3 way, so in the process of troubleshooting it, I tested a voltage reading on the "equipment ground" wire, and got 109 volts. I've never seen this before. Could this be another "ghost voltage reading", and not actual voltage? It is traveling, on the metal box He had it installed in, looking like a "dangerous " situation.
Thanks
 
It was common to use a solenoid tester such as a Wiggy that is low impedance, meaning it loads the circuit and no induced voltage. My Fluke DVM 115 has a low z input, and it’s a much safer meter than the wiggy
 
tom baker said:
It was common to use a solenoid tester such as a Wiggy that is low impedance, meaning it loads the circuit and no induced voltage. My Fluke DVM 115 has a low z input, and it’s a much safer meter than the wiggy
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The use of solenoid voltage testers (wiggys) is not a safety hazard if you don't use them at the service equipment as most of them are rated CAT III. It was always my go to tester for 120 volt installations, including 120 volt industrial control circuits.
 
sparkync said:
The customer I had also had an "equipment ground" wire that was attached to the yoke of his switch. He had it taped black just to insulate it.
He was having problems with the 3 way, so in the process of troubleshooting it, I tested a voltage reading on the "equipment ground" wire, and got 109 volts. I've never seen this before. Could this be another "ghost voltage reading", and not actual voltage? It is traveling, on the metal box He had it installed in, looking like a "dangerous " situation.
Thanks
Click to expand...
Bet he had the other end live. Many homeowners just know number of wires, number of screws. They have no clue that the colors mean something.
 
I checked the ground wire again, after driving 2 ground rods, and separating grounds and neutrals in subpanel. I still had 94 volts to ground according to my
tester. I decided to "jumper" the equipment ground" wire to a true ground source to see if it would trip the breaker. It did not even spark. I'm assuming this was "induced current' and not "real voltage". Would it take 110 or 120 volts to ground to trip fhe breaker, or is this truly only "induce voltage"?
Thanks
 
sparkync said:
I checked the ground wire again, after driving 2 ground rods, and separating grounds and neutrals in subpanel. I still had 94 volts to ground according to my
tester. I decided to "jumper" the equipment ground" wire to a true ground source to see if it would trip the breaker. It did not even spark. I'm assuming this was "induced current' and not "real voltage". Would it take 110 or 120 volts to ground to trip fhe breaker, or is this truly only "induce voltage"?
Thanks
Click to expand...
Adding connections to earth never solves any electrical issue on circuit of less than 600 volts. ...in some cases, adding connections to earth may mask a problem but will not solve it
 
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