Ghost Voltages - Interesting and Confounding! 

I’m not an electrician, but I do some electrical work at home but I wanted to thank you for this video because it was very helpful. I’ll be keeping an eye out for your videos. Thanks.

Thanks. I'm a JM spent most of my apprenticeship doing new commercial construction. That training was invaluable because u have to learn how buildings are built. Newayz. Man, when I moved to service the game changed! U gotta learn and learn quick. I learned this "ghost voltage" 2 yrs ago on a service call to a house. With breaker off I was still getting 30V on a fan/light switch. I intuitively knew it wasnt possible and even showed the homeowner I could lick my finger, ground myself out and touch the hot and nothing would happen. "dont do that handymen". I knew it was inductance but couldn't prove it at the time. Bothered me so I started doing research. In short learned about LowOZ meters and began teaching my apprentice about it. LowOZ is all I pack out now. Always working, always learning! Great video. Thank you.

Nicely explained Mitch, my understanding of electrical circuits has been broadened, this ghost voltage phenomena is clearly capacitive coupling at work, you saved a whole bunch of time, and guess work, thank you.

Learn something new everyday. I spent an hour+ chasing ghost voltage in some 14/3. Almost ended up cutting into drywall to run new wire; thought maybe I shorted a connector with a staple or something.

You can get these phantom voltages in spades from cheapie SMPS modules. I have measured up to 1/2 line voltage on some. Sure, they only produce a few uA and while this is not enough to hurt anyone, it can destroy a MOSFET if it's applied to the gate. So, there are times when you need to take heed of these voltages and do something to mitigate them before you toast some sensitive equipment.

Thank you! I need to buy a Loz meter it seems. I spent 8 hours chasing a phantom voltage the other day! It was 120v, I did IR, and it was fine, so touched it and had no shock, this is when I started looking at this ghost voltage phenomenon. Will I ever need to use the standard volts function again?

It would be interesting to see the reading of an isolation transformer, normally in isolated ground circuits panel if we measure between L1 or L2 and the ground shows 60V when it should be 0V in theory because it is precisely isolated to avoid electric shocks in the patient of hospital.

I had an issue some months ago with a new ceiling fan installation that had a remote control. The receivers kept burning out. When finally installing a standard fan without a remote a family member said that I had approximately 80v of ghost voltage and it was burning this solid-state receiver out. How do I get rid of ghost voltage?

Good eve sir I have now encountered a problem with the LoZ when i test our outlet from the breaker it reads .1 ,and the crt of the lightings also .1 when we insert the circuit of the outlet inside the pipe of the ckt of the lightings,

I didn't like one of the solutions proposed, de-energise adjacent circuits.. If there is an unintended short to one of them you will not then catch it. Regarding the voltage seen , lets say a good quality DVM has an input impedance of 10 M ohms, also lets guess at 100pF stray coupling capacitance. This would be ~25 Mohms at 60 Hz, so on a 110v circuit you would measure about 30v . If we had a 10 k ohm load we were measuring across we would see ~30mV (factor of 1000 Mohm to Kohm). If we looked across a live circuit we would dissipate 1.2 watts. You can buy DVMs with a low input impedance for precisely this job. this quick sum show its not an intractable problem

The measured Ghost voltage measured 79VAC Phantom/ghost voltage from the white neutral wire of the power supply to the N/C white neutral wire of the cord and the same from the green earth wire of the power supply to the N/C green earth wire of the cord measured 79VAC phantom/ghost voltage. The question is why 79VAC is the phantom ghost voltage and not 120VAC? 120VAC real -79VAC ghost= 41VAC difference or loss.