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#72931 - 12/11/06 05:58 PM I have voltage drop
JKWHITTED Offline
Junior Member
Registered: 12/11/06
Posts: 4
Loc: BAY POINT
Coming from the breaker I have 240 but it drops down to 167 when I try to start blower motor. This goes through a phase converter. What could be the problem. I tested from the breaker
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#72932 - 12/11/06 08:36 PM Re: I have voltage drop
ShockMe77 Offline
Member
Registered: 06/11/05
Posts: 823
Loc: Rahway, New Jersey
How far away is the motor from the supply source?

What type and size are the conductors?

Phase converter's.... never worked with them before.
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#72933 - 12/11/06 09:47 PM Re: I have voltage drop
girl germs Offline
Member
Registered: 11/20/06
Posts: 26
Loc: Victoria, BC, Canada
Don't know about this in the "real world" but I remember reading that there needs to be a transformer to adjust the supply voltage before entering the converter, to ensure the correct three-phase voltage (208?)...

is the 167V at the breaker? Have you tested if the three-phase is balancing properly?

hmmm.... *confused*
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#72934 - 12/11/06 11:14 PM Re: I have voltage drop
JKWHITTED Offline
Junior Member
Registered: 12/11/06
Posts: 4
Loc: BAY POINT
it is 50 feet away using #10 wire . it is a soil vapor extractor first time at this site. it is along the railroad and the power is coming from a drop from the railroad pole.
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#72935 - 12/12/06 04:58 AM Re: I have voltage drop
earlydean Offline
Member
Registered: 12/22/03
Posts: 749
Loc: Griswold, CT, USA
What is the blower load?

With the blower off what is the voltage after the phase converter?
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Earl
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#72936 - 12/12/06 05:19 AM Re: I have voltage drop
JKWHITTED Offline
Junior Member
Registered: 12/11/06
Posts: 4
Loc: BAY POINT
460
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#72937 - 12/12/06 05:25 AM Re: I have voltage drop
Zapped Offline
Member
Registered: 10/01/02
Posts: 481
Loc: Huntington Beach, CA, USA
If the supply voltage drops at the breaker, I would guess first that the problem is with the supply, and that the extra load is bringing the problem to the surface. It's probably either the PoCos problem, or you have a bad connection on your side.

Try tightening all lugs on your mains coming into the panel, and everywhere else that you can get to. Make sure all the busses are in good condition and that your breakers are seated properly and the contacts are all in good condition.

If that does nothing, call in your PoCo to check their connections at the x-fer and behind the meter (if you can't get behind the meter yourself because they have it locked out). ALWAYS BE THERE WHEN THEY COME OUT so you can show them the problem UNDER LOAD, or they will not see the problem at all.

I see this problem a lot pretty often,and it's usually a loose connection or a bad main feeder.

Please let us know what you find, and good luck!
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#72938 - 12/12/06 05:41 AM Re: I have voltage drop
JKWHITTED Offline
Junior Member
Registered: 12/11/06
Posts: 4
Loc: BAY POINT
IT IS ON THE RAILROAD .. WE ARE GOING TO BRING IN GENERATOR IF WE CAN'T FIND A PROBLEM. I AM JUST WONDERING IF I HAD A BAD STARTER WOULD THIS CAUSE THIS.. I AM NOT ELECTRICIAN BUT HAVE GENERAL KNOWLEDGE. WHAT ABOUT THE PHASE CONVERTER ITSELF ? THANKS FOR YOU HELP
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