# Utility and UPS in same conduit



## active1 (Dec 29, 2009)

Depends on what the UPS is powering, which NEC article.
700 Emergency system - Not permissible
701 Legally standby system - allowed
702 Optional standby systems - allowed

Emergency systems includes egress lighting and exit signs.

That said if they are paying $XXX amount for the UPS to keep power to something, using separate conduits and J-boxes makes sense. Avoids the slim chance that a major failure in the non-UPS system will cross over. Or with changes a chance that neutrals and hots get mixed up by who ever. 

Less circuits in a conduit is less heating. The UPS computer circuits seem to be always loaded. Probably because they keep adding equipment plugged into the UPS circuits, as it's not an easy just install another UPS.


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## sarness (Sep 14, 2010)

Thanks, I explicitly left out emergency systems as it will not be powering any of that at the remote location, just a couple pieces of low power communication equipment.

As for the UPS, don't think he has any chance of overloading it soon, it's a 40va unit, he has several standalone units at the moment totaling around 20va or so I think.

Right now he's trying to figure out the pathway as it may be tight to get 2 separate conduits there (9 floors) I believe it will be a dedicated conduit for the remote equipment.


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## active1 (Dec 29, 2009)

40 va...
Am I missing something here?
9 floors run for 40 va.
Do they want 100's of hours standby time or what?
How big is the UPS unit?
Why not put a small rack or desktop ups plug in unit unit?


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## sarness (Sep 14, 2010)

Wow, ok, guess I need to spell it out more for such a simple question.

We were talking one day about some things he's working on, one was to set a box on the roof for some of his transmitter equipment powered by 2 circuits, one utility, and one UPS. He was pondering if he would need to have 1, or 2, conduits to power said equipment, even though it's a separately derived source, I didn't think so, only that it needs to be labeled as such.

Right now has a couple racks of equipment powered by several individual UPS's in one location on the first floor. The new UPS will be replacing all the separate units with some moving over to the backup generator side (due to sizing, he can only draw so much from the generator).

If you want more hours you just add batteries or a backup generator, not up the VA.


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## active1 (Dec 29, 2009)

sarness said:


> Wow, ok, guess I need to spell it out more for such a simple question.
> 
> We were talking one day about some things he's working on, one was to set a box on the roof for some of his transmitter equipment powered by 2 circuits, one utility, and one UPS. He was pondering if he would need to have 1, or 2, conduits to power said equipment, even though it's a separately derived source, I didn't think so, only that it needs to be labeled as such.
> 
> ...


Chapter 7 questions are not simple yes / no without details.
In such a situation we placed small UPS units on the standby systems.
The UPS is rated in VA. Such as a small 500va unit could power 40va for 12.5 hours. I'm sure that's what you understand that.

Your welcome.


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## splatz (May 23, 2015)

The VA rating is for the power output, the runtime is separate, it's determined by the amp-hours rating of the batteries and the efficiency of the inverter, and the power factor of the load. 

The crappy little UPS's made to go under someone's desk often have a decent VA rating but only a few minutes runtime.


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## sarness (Sep 14, 2010)

Not that it makes a whole lot of difference, but I forgot a k, it's a 40kva UPS, at least I think it is, it's not a little under desk jobbie, output disconnect I think was 200A.


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## frenchelectrican (Mar 15, 2007)

*A*



sarness said:


> Not that it makes a whole lot of difference, but I forgot a k, it's a 40kva UPS, at least I think it is, it's not a little under desk jobbie, output disconnect I think was 200A.


40*K*va??

single phase 120/240 volts ? 

That is pretty good load and with 9 flights up the floor level I think it may be wiser to run seperated conduit. 

As long it is not classifed as straight 700 I think you can combine it but you have to watch the rating if both are on same time.


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## sarness (Sep 14, 2010)

Blargle, the details keep getting lost for some reason.

The UPS is on the first floor, it suppliers power to various equipment there from a panelboard, in the same area is another panelboard that supplies utility power for other loads.

On the roof, 9 floors up, he want's to mount a cabinet for some radio equipment, and would like two circuits. One utility and one UPS, both probably 20A branch circuits off each panelboard and most likely less then a 10A load.

Two panelboards from same source, no issue, different voltages, no issue either, transformer? Supposedly that's a separately derived source, same as the UPS, and same if from a generator.

There are no article 700 circuits connected to the UPS and the only thing I really see is to identify the neutral.

Last time I dealt with this there were no restrictions for separately derived sources, only that if they entered a common box/cabinet, etc, that it had to be labeled that it was fed from multiple sources.


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