Power went out here in a very odd way the other day, and I can't get
through to power co. for an explanation. Flourescent lights in one
room flickered, dimmed, and went out. Radio lost volume and then went
out. Computer stayed on (with CRT monitor) quite happily until I shut
it down. 'Fridge stayed on. Some incandescent lights would switch on
normally; others wouldn't. Little clock radio quit; light plugged into
same outlet worked. Flourescent in another room remained on.
Electric co. said problem was a neighborhood transformer, and a couple
of blocks were affected, not just my house. So what kind of a failure
is it when some electricity works and some doesn't? I've always
thought of it as an on/off situation.
A few years ago my office lost 1/3rd of the circuits. Turns out a branch
had fallen on one wire of the 3 phase feeding my building.
I was urged to immediately unplug anything that used more than 120 because
it might get insufficient voltage.
Obviously you don't have 3 phase, but I expect something happened to the
transformer so you only got one leg of the 240v.
The simple explanation is that power is supplied to homes with 2 hot wires
and one neutral wire. Half (an over-simplification) of the stuff in your
home uses one of the hots and the other half uses the other. Stoves,
electric heat and AC units use both hots.
If one leg (one of the hots) is not working some of your stuff will work
and the rest of it won't.
And... Any 240 volt devices that are energized would "back feed" the open
leg. Due to loads on the open leg, the voltage would be low, but present. Be
sure to shut off any motorized or electronic appliances that could become
Yup! My f-i-l had that happen. When he turned on the stove, everything
worked. Turned out the feed to his outside box was too short and the
freezing pulled it out of the breaker. The electric company had to come in
and put in a longer feed line.
Yes, thats the term commonly used around here. Brown out. Its
dangerous for some appliances, mostly motors/compressors. Unplug the
Yes this is transformer problem. The beauty of the setup is you can
buron out one of the phases of a transformer, and it will keep doing its
job. It just has less power to give out. Unfortunately if you burn a
few out, and the transformer gets loaded, the voltage will start to drop
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