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enipla
12-20-2007, 08:02 PM
How many amps would a 1500 watt space heater normally draw?

I donít know the ohms, but this is a 10 year old commercial building in the US. I suspect itís 14ga or 12 ga(may need 12 in a commercial building) solid copper with a run of about 75 feet to the panel. Itís a fairly new government building, so I think every thing is up to code. It houses the building inspection department too.

One 1500 watt space heater and one computer is tripping a 20 amp breaker? I suspect there is a draw on the circuit that we donít know about. Or the breaker should be replaced ($8 come on guys. IĒLL do it.)

yes we are having a bit of difficulty keeping our space warm. Building and Grounds finally turned up the heat. 60f is just not good for working at a desk

gazpacho
12-20-2007, 08:08 PM
Watts is volts time current. In the US volts are basically 120 Volts. That is about 12.5 amps. A computer including monitor can be around 500 watts depending on a lot of things. That is about 4 amps. For a total of about 16 or 17 amps.

Q.E.D.
12-20-2007, 08:09 PM
Assuming 120 V, your 1500-watt heater will draw 1500 / 120 = 12.5 amperes.

Q.E.D.
12-20-2007, 08:12 PM
Also, it's important to understand that breakers are to be 80% derated for continuous loading. So, a 20-amp breaker must carry no more than 16 amps continuously or it will trip after a time.

gazpacho
12-20-2007, 08:22 PM
Also, it's important to understand that breakers are to be 80% derated for continuous loading. So, a 20-amp breaker must carry no more than 16 amps continuously or it will trip after a time.So it sounds like the heater plus the computer can be pretty close to where a correctly functioning 20 amp breaker should trip.

enipla
12-20-2007, 08:35 PM
Good info.

We just moved our office in the same building. In my previous Ďcubeí I often had three computers running and a heater. On the same wall/corner within 25 feet there where 4 other computers running. Sometimes also a fan or two.

I canít be sure that it was on the same circuit, but I suppose it was.

As I said, in this new building, the HVAC sucks (well 10 years old, thatís new to me).

This was not a problem for the first few months that we where in our new space. And we all used heaters.

It should not take that long to get the Building and Grounds guys to turn the dam heat up.

It will be real interesting when our PC/hardware guy moves into our space and starts building a dozen PCís at a time.

Heh. Got my UPS.

enipla
12-20-2007, 09:08 PM
As I said, in this new building, the HVAC sucks (well 10 years old, thatís new to me).I should clairfy. This is not a new building to me. We just moved our offices up one floor. It's new in that it was built 10 years ago. About 17000 sq. ft.

Yeah, I guess I would bitch if they hung me with a new rope. But really, EVERYONE complains about the HVAC in this building. That seems pretty common for all comercial structures.

Some parts of the building get down to 60f. Some parts go up to 82f. It's no wonder that some folks have heaters, and some fans. Thank god we can open windows in this place.

No, you can't please everyone, I understand that. But keeping an office space between 68f and 72f should not be that hard to do.

An office mate of mine used one of the automatic doors on the first floor to get in today because his hands where full. They open for about 10 seconds. The Building and Ground guy got pissed at him because "he was letting all the heat out"

On the first floor of a new 17,000 sq ft building.

Umm..... :rolleyes:

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