electric motors
electric motors
(OP)
My church lost power in Hurricane Ike. The power company connected only 2 of the 3 leads to our three phase electric supply circuit (we have some very big AC systems). We have only 80 volts on our electrical outlets. Is it safe to run a refrigerator (designed for 110-120v)at 80v?





RE: electric motors
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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RE: electric motors
And if you run ANY 3 phase motors(A/C) they may be destroyed in seconds.
Keith Cress
kcress - http://www.flaminsystems.com
RE: electric motors
Regards
RE: electric motors
Side note: Some friends living in Houston called because they were supposed to meet my wife at the airport Saturday on her way down to Mexico. They are not going because they still cannot get gas. All of the gas stations in their suburb are still without power so they can't pump. This amazes me; gas stations can't afford portable generators?
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: electric motors
We see refrigeration compressors destroyed, (failed) if you rather, in less than a minute due to single phasing and often the O.L.s don't trip. And when a hermetic or semi-hermetic have an insulation problem it is a melting issue that can wreak havoc with the entire system. Acids are created in the melting that attack everything. All you need is the refrigerants to exceed some fairly low temperature and the acids form.
If the the motor is started in a single phasing situation it is a race with the OLs that the compressors often win. (Lose!)
Keith Cress
kcress - http://www.flaminsystems.com
RE: electric motors
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: electric motors
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RE: electric motors
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RE: electric motors
Bill
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"Why not the best?"
Jimmy Carter
RE: electric motors
The original post stated "Is it safe to run a refrigerator (designed for 110-120v)at 80v?"
Is there some reason to think this refrigerator is 3 phase?
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RE: electric motors
RE: electric motors
No there are no 120V 3 phase appliances like that. 120V would explicitly imply single phase.
BobM3,
I think he was meaning he was getting an unusually low voltage on the 120V circuits in addition to having one of the lines down, which indicates an additional serious problem, making it unsafe to operate anything.
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: electric motors
Keith Cress
kcress - http://www.flaminsystems.com
RE: electric motors
RE: electric motors
RE: electric motors
I suspect that he has a utility version of the blown main fuse syndrome. The third phase is being back fed by a series connection through phase to phase connected loads.
Thanks LionelHutz for the excellent suggestion. It may well be only one phase that is affected.
Bill
--------------------
"Why not the best?"
Jimmy Carter