ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by tortuga - 03/28/24 05:57 PM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 260 guests, and 19 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 3 1 2 3
#191846 01/16/10 12:53 AM
Joined: Jul 2002
Posts: 241
S
SJT Offline OP
Member
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

Joined: Mar 2007
Posts: 404
Member
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.

Joined: Oct 2000
Posts: 4,116
Likes: 4
Member
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

Joined: Apr 2002
Posts: 7,381
Likes: 7
Member
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
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
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
Joined: Oct 2000
Posts: 4,116
Likes: 4
Member
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

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
The last pre-fab cubicles were arranged with three 20-amp circuits shared over five cubicles, if that's any help.

Joined: Jul 2002
Posts: 241
S
SJT Offline OP
Member
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

Joined: Jul 2007
Posts: 1,335
S
Member
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 02:18 AM.

"Live Awesome!" - Kevin Carosa
Joined: Mar 2007
Posts: 404
Member
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 03:01 AM.
Page 1 of 3 1 2 3

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5