I'm curious. Why would 60hz and 50hz be different?
My reason to post this is because of what happened yesterday in a nearby
town. (See below)
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I dont believe this is a Memorial Day tradition, but a small rural town
had a big dinner cooking for the whole town. For a reasonable price,
you could get a complete meal with all the fixings and dessert too.
One problem. Many women in town converged on the town's community
center building, all equipped with an electric roaster filled with food.
They plugged in roaster after roaster, and had to move several of them
after tripping some breakers. They finally got them all working. There
were around 25 roasters total, but not all were plugged in at once.
However they did manage to plug in about 15 of them. Then they plugged
in a half dozen huge industrial sized coffee pots, cranked up the walk
in freezer for the ice cream, turned on all the lights in the large
dining room, and since it was a hot day, they turned on the air
conditioner.
For awhile, everything worked fine. Right when the people were coming
in to eat, the place went dark. No lights, all the roasters went off,
the air conditioning went off, the water stopped flowing from the sinks
(well pump), and everyone was eating in the dark. Minutes later the
fire department arrived with a large generator. The generator failed
after 3 minutes of use and although the gas engine still ran, it would
not put out even one volt of power. (They had hooked it to the
building's mains).
About that same time, the electrician arrived, several neighbors whose
homes are nearby came over and said they had no power in their homes.
OOPS!!!! The electrician confirmed that there was no power coming from
the pole to that building, nor to all the homes for a couple block area.
It was a hot day, as well, so lots of people were running Air
conditioners.
Yep, all those roasters and coffee pots and ACs and other stuff, roasted
the pole transformer.
It took the power company about an hour to arrive, and another 20
minutes to locate the drivers of cars that were parked in the way of
power company's trucks. (by that pole). They finally got to the top of
the pole, when one of the workers began to remove wires, he touched the
transformer with his bare hands and burned his fingers. (by this time
the power had been off for over one and a half hours, so it had cooled
down some).
They removed the 25 KVA transformer and replaced it with a 37.5 KVA
model.
When I got home, I did some figuring. Those roasters (most are old),
consume about 14 amps each. Those huge coffee pots are not much less.
So, lets just use round figures and say they averaged 12 amps (minimum)
per unit. 15 roasters, and 6 coffee makers is 21 devices. That works
out to a draw of 252 amps at 120V AC. Add to that the freezer, the AC,
the lights, and then add all the stuff that was running in homes along
that block.
(The building has a 200A main)
It's no surprise that the transformer failed.
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Comment - Personally, I think that 37.5 transformer should be dedicated
ONLY to the Community Center, and another one (or several) should be
added for the nearby homes. "Women with electric roasters are dangerous
to the electrical system
".