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#191846 01/15/10 11:53 PM
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SJT Offline OP
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Is there a rule of thumb for the amount of circuits to be ran in an office setting with approx. 10 cubicles. Each would have a computer, monitor, and printer. I'm going to figure 1 amp for a single computer, and 1 amp for a single monitor. Are the desktop printers in the range of 2 amps? The computers, I would think should be figured with continuous duty, 125% added in. Thanks

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CRT or LCD monitor? Inkjet or laser printer? Computers can vary a lot, depending on how much kludge is in the box... A standard computer is probably around 100W or less, but professional workstations with multiple processors and hard drives can be more.

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One thing I'd ask is if the people will be allowed to have portable heaters. Some people can't live without them. There might be a copy machine that will need its own circuit too.

Bill

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First & foremost IMHO, the following info should be available to the EC. Are cubicles 'new' or 'pre-owned'; equipped with factory' wiring harnesses? Or is the EC doing it from scratch?

Factory units must be wired to mfg instructions.

Otherwise, if it's a 'scratch' job, & the budget range of the job, 5 amps per ststion, 3 stations per 20 amp (derated); 4x20amp circuits would be my minimum.
Now...electric heat? 1 circuit each station! Toaster ovens? Don't laugh, I've been there!



John
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I think you better bump that 100w up a bit. The PC that I am typing on now is pulling a tad over 180w just sitting here and when the CPU really cranks up (IE editing a video file) it goes over 200. That is a 2.8gz single core computer, 15" LCD monitor, a switch and a router. Ink Jet printer idle.
Just for Gee whiz info the Kilawatt device says I used 459 KWH in 2516 hours.

That translates to at least 2 amps

If they are going to have a laser printer, add 10 amps.

What is the wiring method? If they have an under the floor raceway/duct system you have a chance to upgrade. Nobody ever got in long term trouble putting too much power into an office but sometimes it takes a few years to prove them right. Going for the minimum usually bites you in the butt fairly soon.


Greg Fretwell
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Originally Posted by HotLine1
Now...electric heat? 1 circuit each station! Toaster ovens? Don't laugh, I've been there!
Don't forget Coffee maker(s)

smile
Bill

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The last pre-fab cubicles were arranged with three 20-amp circuits shared over five cubicles, if that's any help.

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SJT Offline OP
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The cubicles were pre-wired with factory assemblies. They may be the 8 pin type. It was set up with 2 circuits, and they want a third circuit. Looks like the in house Electricians will have to open the existing outlets to find where the circuits originate from.
Good Weekend

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Rule of thumb for general open office is 4 cubicals. If you suspect extra electrical loads like coffee makers, boot dryers and such, 3 per circuit.

Last edited by sparkyinak; 01/17/10 01:18 AM.

"Live Awesome!" - Kevin Carosa
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Originally Posted by gfretwell
I think you better bump that 100w up a bit. The PC that I am typing on now is pulling a tad over 180w just sitting here and when the CPU really cranks up (IE editing a video file) it goes over 200. That is a 2.8gz single core computer, 15" LCD monitor, a switch and a router.


Ok, let's say 200W... My two computers (one Mac Mini and one AthlonX2) and CRT draw 320W. Figure 60W on the CRT, 40-60W for the Mini and 200-220W on the Athlon. Could do more comprehensive tests, but that would require a shutdown.

Last edited by noderaser; 01/17/10 02:01 AM.
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