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What causes weird voltages at receptacles?
Ghost voltages can be caused when energized circuits and non energized wiring are located in close proximity to each other, such as in the same conduit or raceway. The capacitance between the connected, hot conductor and the floating conductor forms a voltage divider in conjunction with the multimeter input impedance.
What causes a ground wire to spark?
Most likely though, since the ground doesn’t blow the breaker on it’s own, the junction box is powered somehow. In one way or another, power is feeding through that box. It could be from the sheathing of the BX or any stripped or loose hot wire touching any of the system.
Should there be voltage on a ground wire?
You have to measure neutral-ground or hot-ground. If neutral-ground voltage is about 120 V and hot-ground is a few volts or less, then hot and neutral have been reversed. Under load conditions, there should be some neutral-ground voltage – 2 V or a little bit less is pretty typical.
What does phantom voltage mean on a light bulb?
It is not real, usable voltage, and actually means the wire is disconnected. The easy way to test for phantom voltage is use a less sensitive meter, or put a tiny load on the circuit. The tiny load will quickly extinguish the phantom voltage. just screw in a light bulb socket adapter plug in an incandescent night-light with a switch.
Why do I have phantom voltage in my house?
Sometimes homes have grounded-type wires run throughout the home, but the ground wire, for one reason or another, is either not connected to the devices (receptacles, switches, light fixtures etc), or the wire just simply isn’t being used–or even possibly disconnected somewhere. Homes wired in the early 60’s often have this condition.
What should the voltage of a light outlet be?
If so, isolate those items, and test the light outlet again, is the voltage higher or lower than the initial 80v? (say +/- 3v) when tested HOT to NEUTRAL If the voltage on #4 goes up or fluctuates, greater than a few volts, then the issue is most likely upstream and this helps you identify where to check first.
What does 80v mean on an electrical outlet?
Contact an electrician if any of this is even remotely questionable. You used a DVM? 80V sounds a lot like phantom voltage, induced by nearby wires. It’s a bit like how a crystal AM radio can use the radio waves itself to power a tiny earpiece.