View Full Version : Weird voltage readings.
trasafofc
Jun 23, 2008, 07:35 AM
I am trying to help a friend of mine with an electrical issue and I am not able to. He has a sun room that has a dedicated 15 amp circuit running to it but lost power in the sun room for the outlets and ceiling fan and outside light. I have tested the breaker and its getting 120V to neutral and ground. But when I test to the first outlet where the feed comes into the sun room I get 120V to ground and 117V to neutral, and if I test my hot coming in to the black and white wire going to the next outlet I get 30V on both... is this a open neutral or is my hot and neutral touching somewhere?? Im lost... any help you can give me is greatly appreciated...
Credendovidis
Jun 23, 2008, 07:52 AM
First if the wiring has not been changed, and the problem was not there before, but has suddenly occurred :
There is a bad connection between the neutrals in the (first) outlet where the in and out neutrals show a voltage difference.
As a result the voltage on the not properly connected neutral lines starts to float by capacitive action or connected equipment, and reduces the difference between hot and neutral.
If the wiring was changed and the problem occurred afterwards :
As per the first suggestion, but now also check if anywhere the neutral and earth wires have been swopped. If that turns out to be the case, your earth is a poor one!
Success !
donf
Jun 23, 2008, 08:16 AM
Please try it this way.
First, unplug all wires from the receptacles in the sun room. If a wall switch connects the to the light, turn the switch off. With everything off, take your voltage reading you should see any where from 132 to 118 VAC. If you do not, disconnect the wall switch. If it is a glo switch, the LED could be shorted out. I had the same problem the other day.
Whit the switch disconnected, take your voltage reading.
KISS
Jun 23, 2008, 08:24 AM
You can also take a reading from the good outlet neutral, to the bad outlet hot. If the reading is correct, then open neutral.