We have a client that would like to have a UPS on two office computers.

2 problems exist. First, he doesn't want the bulky and unsightly UPS on the floor or visible in the room. Second, he wants to protect both machines which will be physically located on opposite sides of the room.

My solution is to put the ups in the rack and run two outputs into two separate powerlinks as essential an in wall rated extension cable.

In theory this feels like a good, and might a say genius, solution. The clients IT guy had to some concerns about extending the wire. This seems like a valid concern based on wire gauge and heat etc.

Thoughts?

We have a client who is running his entire theater on a UPS... it can be done. This UPS takes up two racks, each one of which would swallow up our average rack.

Put the UPS in the room with the circuit breakers. Run power from there to outlets at each computer. Done.

I don't understand the reference to heat being a problem. 14 ga wire, which is standard for extending an outlet as you would do if you had the UPS in the room, is NOT going to get warm when powering a computer. A toaster, well, maybe. A computer? No. Get out your table of wire gauges, diameters, resistance, etc (you DO have that as part of your engineering armamentarium, no?) and calculate the amount of power the wire would dissipate per foot of wire for, say ten amps, which is way more than a computer would draw. When that figure turns out to be exceedingly low, you will have proof that there will be no problem.

No problem, if you can get the Romex where you need it.

Yes, it is genius...And I do it on nearly every installation ;-).

I install a rack UPS and have Sparky wire 12AWG "extensions" from an inlet near the UPS to an outlet at the piece of equipment I want to support.

You might want to have Sparky check the NEC.

The gauge of wire that is installed is not only supposed to be large enough to carry the necessary current, its gauge signals to subsquent electricians how much current they should expect will come from that piece of wire. It's my understanding that any such branch from an outlet that comes from a breaker (naturally) is supposed to be 14 ga. Don't tell an electrician, by the size of the wire that's installed, that 15 amps are available when only five or ten are.

Sections 210.19(A), 215.2 and 230.42(A) require the conductor to be sized no less than 100% of the noncontinuous load, plus 125% of the continuous load. I  check the breaker, but also look to be sure the wire is sized correctly for the breaker to verify what that circuit will carry.

+1

Only thing I would add is that you should make sure the UPS Supported receptacle is marked that it is powered from the UPS (ie. Red Receptacle with label "UPS Supplied").

Just in case some body wants to do work on the receptacle they will know to unplug it from the UPS.

eric,
I was remembering what I first learned over a dozen years ago about wire sizes on branch circuits. I guess I confuzzled that with an overseas spec I recently ran into where the wire's size is also limited to a maximum size for the available amperage. The reasoning is that you don't want an electrician to run across, say, an 8 gauge wire coming from a branch from an outlet on a 7 amp breaker (Euro 230V value) because the electrician would then expect that A LOT of current was available, when it was not.

Ernie, I fell you are a little confused with wire gauge vs. current available.

Its very common to up size the wire to combat voltage drop but no "qualified" electrician would look at wire size and from that alone figure out available current.

In theory every outlet in the house has unlimited current at it. Breakers are the method that we us to limit the current to safe levels to protect the wire and device from damage

Awesome guys. Thanks!

I do it all the time with projectors, don't see why it should be a problem, just label it as said before.