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#20610 - 01/17/03 06:29 AM UPS/Generator help
ZR600 Offline

Registered: 04/02/02
Posts: 48
Loc: Stevens Point, WI, USA
I have a problem (well many but I will just deal with this one right now). Power at this plant is 208/120 three phase. The generator is 240/120 single phase. The problem is this plant now added a UPS and the voltage to this UPS is out of spec. It sees 204 to 208 on regular power and 230 on the generator power. The UPS will not switch over in this condition. What can I do to get this voltage in spec. Maybe a trans? If so how? I have very little experiance with this so any help would be great. Thanks.........Brian

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#20611 - 01/17/03 07:04 AM Re: UPS/Generator help
Trainwire Offline

Registered: 03/15/02
Posts: 364
Loc: Strasburg,PA,USA
How many KW's are we dealing with here.


#20612 - 01/17/03 09:10 AM Re: UPS/Generator help
ZR600 Offline

Registered: 04/02/02
Posts: 48
Loc: Stevens Point, WI, USA
I think it is a 6.9 KVA unit. I think I got it to except the voltage difference by setting the incoming voltage on the unit to 220/110. Must be a happy medium? I still would like to figure out what to do if I could not have got it to work by changing the settings. Thanks.......Brian

#20613 - 01/17/03 09:30 AM Re: UPS/Generator help
BuggabooBren Offline

Registered: 11/15/01
Posts: 336
Loc: NM
I doubt if this is in the same rating class as the one you're referring to, but there's a recall on some "Back-UPS CS Uninterruptible Power Supply devices" as noted in this article: which states:

A Rhode Island company is recalling about 900,000 backup power supply devices that can overheat and cause a potential fire hazard.

American Power Conversion Corp., of West Kingston, R.I., has received six reports of overheated units melting their outer casings and three reports of minor property damage, the Consumer Product Safety Commission said

The recalled Back-UPS CS Uninterruptible Power Supply devices, commonly used to protect computers in case of power failures, include the Back-UPS CS350 and the Back-UPS CS 500 models.

Retailers, computer and electrical distributors and catalogs nationwide sold the power supply devices from November 2000 through December 2002.

Consumers should immediately stop using the devices by turning off power to all connected equipment, turning the Back-UPS CS off and unplugging it from the electrical outlet, the company said.

Consumers can receive a free replacement unit by contacting the company at 1-866-272-7359.

#20614 - 01/17/03 09:37 AM Re: UPS/Generator help
resqcapt19 Offline

Registered: 11/10/00
Posts: 2209
Loc: IL
Looks like a good application for buck/boost transformer .

[This message has been edited by resqcapt19 (edited 01-17-2003).]

#20615 - 01/17/03 10:44 AM Re: UPS/Generator help
Ron Offline

Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
I would completely agree with the buck boost transformer. Consider what you are asking the UPS to do, when you give it two different voltages to work with. It has a tollerance that it considers unacceptable, and 204-230 is well outside of what I would want the UPS to make descisions for regarding my critical load.

#20616 - 01/17/03 01:45 PM Re: UPS/Generator help
ZR600 Offline

Registered: 04/02/02
Posts: 48
Loc: Stevens Point, WI, USA
How would I hook this up with a Neutral that is needed at the UPS? Anyone got a wiring diagram?..............Brian


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