Parallel ups feeders

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RUWired

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Is it possible to parallel two different u.p.s. systems together for a brief period of time( 3-5 seconds )without any transformer inpedance promblems.I need to relocate a feeder to a panel and would like to do so without an interuption.The distance to each of the different u.p.s.systems is about 250' from the commom panel.
Rick
 
Unless the UPSs are designed to be paralleled with each other, then no, this will most likely result in bad things happening.

Assuming the two UPSs have a common supply (or at least their supplies are in phase), the way that can work is to take the UPSs down to manual bypass, then do the break before make changeover. You'll have a few seconds with no UPS protection, but the smoke will stay in the UPSs and not be released.

I'm sure you know all this, but be very very sure that phase order is correct before the paralleling, or you will be an arc flash statistic.
 
dbuckley said:
Unless the UPSs are designed to be paralleled with each other, then no, this will most likely result in bad things happening.

Assuming the two UPSs have a common supply (or at least their supplies are in phase), the way that can work is to take the UPSs down to manual bypass, then do the break before make changeover. You'll have a few seconds with no UPS protection, but the smoke will stay in the UPSs and not be released.

I'm sure you know all this, but be very very sure that phase order is correct before the paralleling, or you will be an arc flash statistic.
Click to expand...


That damn pesky smoke...always looking for a way to get out. Sort of like the commercial about risk, it is always awake and just keeps on looking for a way out.
 
I have UNDER VERY SPECIAL CONDITIONS and with lots of meetings and caveats, paralleled numerous systems. BUT and I stress the BUT if you are asking this question I would suggest you not do this.

Generally if the UPS's can be bypassed to utility it is easier with the right equipment.

If there are two different sources (utility generator) the paralleling is MUCH more difficult.

But as I mentioned in either case you have to own certain equipment, and KNOW WHAT YOU ARE DOING.

IM me if you would like more information.
 
Eaton Powerware UPS's can be paralleled, but you need a special cabinet to tie the two together. The parallel cabinet prevents one UPS from backfeeding the other.
 
Pierre C Belarge said:
That damn pesky smoke...always looking for a way to get out.
Click to expand...

It sure is. Any time you mix power electrics with electronics the opportunities multiply, and paralleling a couple of random UPS systems seems as good a way to get the smoke going as any...
 
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