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#12916 - 08/21/02 10:08 AM outlet load?
electricdope Offline
Junior Member

Registered: 08/21/02
Posts: 2
Hello, I'm new to this forum, and as you can tell by my name, I'm a dope about electrical topics.

My question is about my computer work area. I currently have a PC, monitor, scanner, printer, cordless phone, speakers, shredder, and radio all plugged into a single power bar. No problems. I'm pretty sure the outlet is only 15 amps, so I'm wondering if I'm pushing my luck. Is there a simple calculation I can do to determine if I'm approaching the maximum load? For example, can I just add all the amp ratings of the components to see if it's over 15? It so, I still the problem where some components give a wattage and some give amps only, and some don't give either.

Help please?

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#12917 - 08/21/02 10:39 AM Re: outlet load?
George Corron Offline

Registered: 05/16/01
Posts: 728
Loc: Lorton, Va USA
add all the watts together and divide by the voltage. (ya wanna be correct then multiply by 1.25) that will give your amperage at full load. If the nameplate states the amperage, just add it up.

None of that stuff usually adds up to much, but all of it should have a UL tag. We could get into a lot of possibilities here, but that's the basic. The 1.25 is because all the 'stuff' you mentioned is solid state, so off the top of your head you have to figure for an 80% power factor.

#12918 - 08/21/02 01:17 PM Re: outlet load?
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England

AS George said, add up the power and/or current ratings to be sure.

In very general terms, PCs and their associated peripherals, radios, cordless phones, fax machines and stuff like that draw a relatively low current, so running them together on a power strip shouldn't cause an overload.

The things to start being more careful about are any appliances which incorporate some sort of heating element (e.g. room heater, coffee maker) or a heavy motor (e.g. A/C unit).

#12919 - 08/21/02 02:04 PM Re: outlet load?
NJwirenut Offline

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
The only PC peripheral that might draw substantial current is a laser printer. These things have a large quartz lamp inside (like a photocopier lamp) to heat up one of the rollers. Because of the possible voltage sags when the lamp cycles on, laser printers should really be on their own circuit.

#12920 - 08/23/02 12:30 PM Re: outlet load?
electricdope Offline
Junior Member

Registered: 08/21/02
Posts: 2
Thanks to those who replied. I will try the calculation you provided George.


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