ups

[Devo2]

I got an old UPS from work, I figured it would have an inverter that might be handy but it seems the battery bank may still be good.  It is 240 dc. If I wound a windmill to put out 240 volts could the UPS be used as a battery bank/inverter.

Devin

[bob g]

short answer is likely yes, but

the long answer is likely "no friggin way"!   

240vdc is just flat deadly in so many ways ways, the least of which  is not the battery bank.

one bad cell in the string can fail in a very dramatic and spectacular way.

i would think about this long and hard before doing it, maybe do a 48volt windmill and
boost the voltage to 240dc for charging, at least that gets the safety factor within reason
at the mill, down the tower and to the battery shed to acceptable levels, from there
i would keep the batteries in their oem containment

bob g

[Bruce S]

I got an old UPS from work, I figured it would have an inverter that might be handy but it seems the battery bank may still be good.  It is 240 dc. If I wound a windmill to put out 240 volts could the UPS be used as a battery bank/inverter.

Devin

Devo2.
Do you have a model of the UPS? how big is this unit? even the Mega sized Matrix built by APC is only 48VDC. Most of the smaller units are 24Vdc and 12Vdc.
WOW 240Vdc is as Bob g said, dangerous , to say the least. This stuff will jump most normal contacts and DC kills at those levels.

Bruce S

[zap]

Tripp Lite SU20K3/3X
http://www.tripplite.com/en/products/model.cfm?txtModelID=3646

I think Avaya makes a few also.
And I seem to recall a few that were specific to the telco industry years back?

[Devo2]

[/quote]
Devo2.
Do you have a model of the UPS? how big is this unit? even the Mega sized Matrix built by APC is only 48VDC. Most of the smaller units are 24Vdc and 12Vdc.
WOW 240Vdc is as Bob g said, dangerous , to say the least. This stuff will jump most normal contacts and DC kills at those levels.

Bruce S


[/quote]

One box i believe is a battery as it's heavy, it says battery 240 volts DC, Current 23 Amps DC, Capacity 5 ah it says Comet exb mge on it & made in France.

The other box has a model # 5103383300 they plug together & it has battery meters & such on it. It says Battery 240 volt,45 amp. Voltage input 187-257 volts AC, 61 Amps AC 50/60 hz, Output 208 VAC 55AAC-power 600W/11400VA. I originally thought it may have a usable pure sinewave inverter in it?

Devo

[Bruce S]

One box i believe is a battery as it's heavy, it says battery 240 volts DC, Current 23 Amps DC, Capacity 5 ah it says Comet exb mge on it & made in France.

The other box has a model # 5103383300 they plug together & it has battery meters & such on it. It says Battery 240 volt,45 amp. Voltage input 187-257 volts AC, 61 Amps AC 50/60 hz, Output 208 VAC 55AAC-power 600W/11400VA. I originally thought it may have a usable pure sinewave inverter in it?

Devo
[/quote]
Devo2
Okay MGE units are normally pretty big. The unit we have here uses multiple racks of 12Vdc batteries arranged in 48Vdc setups, there 10 sets in ours.
The people who work on these use Fluke meters with some seriously insulated meter probes and high voltage thick insulated gloves that go to their armpits.
If you have the chance take a pic of the inside of the battery box. The other side does indeed carry a wonderful 3 phase ultra-pure sine-wave inverter. If it's the same as I think the other Comet lines are.
The model # didn't work even with MGE product line.
NOTE: MGE has now merged with APC so it might start getting hard to get info.
 Hope this helps a little, and that you don't take offense with us posting about being cautious.

Bruce S


 

[bob g]

there are many of the larger ups systems around, surplus for free or little money, problem is they are almost always
high voltage units,

the apc matrix units are 48volt as are most of the smart series over 2kva, however
the symmetra series are 192vdc

the best/exide are often 240vdc in the larger sizes

the lieberts are commonly 192volts even in smaller sizes

48vdc will bite you, but not kill you under normal circumstances, but
i hate anything over about 100vdc, most especially if batteries are involved.

and i work frequently with 480vac three phase power panels!

of the two i am much more comfortable with the 480 three phase

bob g

[Jon Miller]

If it were me I would sell the MGE unit and buy a lower voltage APC unit and charge batteries at the lower voltage of the APC unit.

240VDC is to high to play around with.

The APC units are solid and cheap.

Regards

Jonathan

[dnix71]

We have something like that in a room in the building to back up lights and servers in a bldg that is half a city block long.  It's powered by a room full of batteries.

That isn't something you want to mess with at home. The high voltage bank is needed to keep the current draw to safe levels and eliminate the need to step up or down the input voltage much.

The batteries are the main cost. We don't even mess with that now. Corporate in Minnesota contracted out to someone to do all the divisions' UPS backups. We have to hire out locally for the 400KW Volvo deisel genset out back that backs up the backup. The batteries are only good for about 1/2 hour. If we don't get the Volvo up and running within 30 minutes, something crashes.

[diyrob]

there are many of the larger ups systems around, surplus for free or little money, problem is they are almost always
high voltage units,

the apc matrix units are 48volt as are most of the smart series over 2kva, however
the symmetra series are 192vdc

the best/exide are often 240vdc in the larger sizes

the lieberts are commonly 192volts even in smaller sizes

48vdc will bite you, but not kill you under normal circumstances, but
i hate anything over about 100vdc, most especially if batteries are involved.

and i work frequently with 480vac three phase power panels!

of the two i am much more comfortable with the 480 three phase

bob g

 


Bob,

Comfortable is not the term I would use to decribe standing in front of an open 480 volt panel.  Check this video.  This looks like a quick and lethal way to get a "coppertone tan".
http://www.youtube.com/watch?v=-iClXrd50Z8