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Uninterruptible Power Supply (UPS)

Uninterruptible Power Supply (UPS)

Uninterruptible Power Supply (UPS)

(OP)
Does anyone know of any UPS manufacturer that provides a UPS with the following characteristics:
1- Input: 120/208V, 3PH
2- Output: 120/208V, 3PH
3- Capacity: 30KVA
4- Battery: 1 to 2 hours backup time without need for  external battery pack

5- Power Factor: 1 or very close
6- Harmonics: Good THD<=3%
7- Good Crest and Surge factor

Thanks in advance for your help

RE: Uninterruptible Power Supply (UPS)

What IR said -- there's lots of manufacturers that could meet every point on your list EXCEPT the battery run time -- I'm not aware of any UPS system that could hit 1 hour without an external battery.

RE: Uninterruptible Power Supply (UPS)

(OP)
thanks guys for your prompt reply. I guess I'll have to use an external battery or combine many UPS'

RE: Uninterruptible Power Supply (UPS)

Just curious - why do you not want an external battery?
For this spec, your battery will probably weigh somewhere around 1500 to 3000lb.

RE: Uninterruptible Power Supply (UPS)

i am with ahlehman..

there is no such thing as internal battery for 30kVA UPS units and specially for 1 hr.

You need to decide, which one you want, so called 'internal battery' (not requiring additional cabinet?) or 1 hr back up. Can't have both.

RE: Uninterruptible Power Supply (UPS)

Check out Toshiba UPS's. http://www.tic.toshiba.com/productpages.php?prod=4200FA&family=UPS I just worked on some for backing up portable radar sysems, and they wanted 1 hour of backup as well, albeit 25kVA. Toshiba did a custom design for this and were excellent to work with.

"Venditori de oleum-vipera non vigere excordis populi"


RE: Uninterruptible Power Supply (UPS)

We recently installed a redundant UPS supplied by GE Digital Energy - formerly IMV - and found them to be good to work with. Our system used two standard 80kVA modules but a non-standard multi-string battery.

30kVA is at the bottom end of the GEDE size range, but the technology is common across the range. As with everything, you get what you pay for, but by dealing direct with GEDE in the UK we paid a fair price for a good product.



----------------------------------

If we learn from our mistakes,
I'm getting a great education!

RE: Uninterruptible Power Supply (UPS)

Are you sure you want your pf around 1?  Most UPS's I'm familiar with have a .9 as standard.  Now depending on your load, you need to be careful.  I've been hearing more as of late that power factor corrected power supplies being the cause of the system power factor to go leading and then eventually causing the UPS to fail.

Mike

RE: Uninterruptible Power Supply (UPS)

APC is the only mfg. I know that rates their equipment at 1.0 pf. APC's white papers state that most IT loads are near 1.0 pf so they rate their UPS's accordingly. I think this was just an attempt at simplification of sizing requirements for the IT folks (to whom they cater).

It could get you in trouble if the UPS is fully loaded. In most cases I see around 0.9 lag aggregate.

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