I was at the tire shop the other day and had to use the restroom. While
in the restroom the lights suddenly went to half brightness, and I heard
their air compressor kick on in the shop. When I went back in the shop
I saw the compressor, and it's quite a large beast, with a hefty motor.
But that near brownout seemed excessive. It's normal for lights to
flicker a little when a large motor kicks on, but these lights went to
half brightness as the motor kicked on.
I know it could be wire size inside the building, or the cable from the
pole to the building, but I kind of suspect the pole transformer more
than the wires. The reason being that I can see the overhead wires from
pole to building, and they are very thick. If it was wiring inside the
building, it should not affect one 60W bulb run from 120V, when the
compressor is run off 220V, which should be a breaker coming right off
This is a small town in a rural area, so the power company does not
really upgrade stuff very often. Yet, this building is fed off of a 3
phase line that serves several other industrial buildings, including a
large factory which closed it's doors a few years ago. Since that
factory closed, there should be adequate high voltage on the supply side
of the transformer, thus it would seem to me that the transformer is
inadaquate or weak.....
There is no way to know the cause, since I dont work there or anything,
but I'm just curious what others think.