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Posted By: wa2ise power failure but lights dim - 08/14/20 05:15 PM
And not a bad neutral.
[Linked Image from wa2ise.com]
Some excitement today, a thunderstorm. we had a power failure today where the lights didn't completely go out. Line voltage ended up varying from 20V to 50V and at a peak of 70V. Seems lightning hit the distribution lines, and took out only two of the three phases. And I was on one of the impacted phases. Seems I was seeing power leakage thru power customers that get fed all 3 phases, and have loads connecting from one phase to another (208V). That would make a leakage path that would work its way back thru pole pig transformers back to the distribution lines and then to my pole pig.

I shut down my air conditioners and fridge, as compressors really don't like under voltages. Computer power supplies don't much like it either.

Later, once Pubic Service fixed it, saw a picture on FB of line crews in bucket trucks attending to the lines. And saw that 2 of the 3 phases were broken. One of the broken phases was the one I'm on.

To add to the fun, some LED bulbs could operate up to half their usual brightness during this event. Others didn't light at all. Incandescents showed most directly the voltage variations.
Posted By: gfretwell Re: power failure but lights dim - 08/14/20 08:16 PM
Back circuits can do strange things. Hopefully everything survived. I have seen 3 phase motors limp along on 2 fairly often but they are hot and not really doing well in the power department.
Posted By: HotLine1 Re: power failure but lights dim - 08/18/20 06:45 PM
Just be thankful you don't have JCP&L.

FWIW, the Municipal Complex here was dark from Tuesday afternoon until early Friday morning from a tree down and four poles. 26KV, 13/2KV, a few pole mounted transformers and capacitors.

Crew from Oklahoma did the replacements.
Posted By: Dixonedwards Re: power failure but lights dim - 02/18/22 06:01 PM
One of the most aggravating situations is when your lights are on yet half or all of your house's power outlets are off. This is frequently the result of a defective appliance touching an safety switch. Each equipment should be disconnected from the circuit.
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