View Full Version : How to calculate the electrical lighting and appliance load, in single family house
amaasd2000
Dec 15, 2008, 08:29 AM
I have to calculate this in Kilowatts. The formula has to be within NEC guidelines. Using Article 220. Please simplify the formula. I just need to know kw and not kilowatt hours
tkrussell
Dec 15, 2008, 09:50 AM
Using traditional Ohm's Law:
P (KW)= EI/1000
Kilowatts = Volts times amps divide by 1000
For example:
P= 240 volts times 50 amp = 12,000 watts divided by 1000 = 12 KW
I have to ask, and not meaning to be offensive or condensending, but if you can understand Article 220, but did not know this?
Article 220 makes us electricians run screaming into the night, until we finally get it.
amaasd2000
Dec 15, 2008, 10:46 AM
Using traditional Ohm's Law:
P (KW)= EI/1000
Kilowatts = Volts times amps divide by 1000
For example:
P= 240 volts times 50 amp = 12,000 watts divided by 1000 = 12 KW
I have to ask, and not meaning to be offensive or condensending, but if you can understand Article 220, but did not know this?
Article 220 makes us electricians run screaming into the night, until we finally get it.
I have the material, but don't fully understand it. I do go screaming into the night. I apologize for a mistake, that I may have made. My final exam is going to have us fill out a utility service load form for KW. A single family house and a multifamily dewelling. I need a simple formula to figure the load of: lighting, heating, and electrical recepticals. I apologize for not stating the question properly. Thanks for your first reply. I'm nervous about this exam.
tkrussell
Dec 15, 2008, 02:25 PM
Based on this:
I have the material, but don't fully understand it.
Then:
I'm nervous about this exam.
You should be.
How did you get to the point of taking an exam and not understanding the material?
What type of exam are you taking?
If you need to fill out a utility load sheet, NEC Art 220 usually does not apply. They want real loads, not any derated as allowed by Art 220. The utility will apply their own demand factors against the actual loads you enter on the form.
amaasd2000
Dec 16, 2008, 07:55 AM
Based on this:
Then:
You should be.
How did you get to the point of taking an exam and not understanding the material?
What type of exam are you taking?
If you need to fill out a utility load sheet, NEC Art 220 usually does not apply. They want real loads, not any derated as allowed by Art 220. the utility will apply their own demand factors against the actual loads you enter on the form.
Thanks Again, for the help you gave me. I'm taking a nighttime adult school course. It's accellerated and you meet once a week. You don't get much time to review things. In the end it worked out.
AVRAAMG
Dec 18, 2008, 03:22 AM
I have to calculate this in Kilowatts. The formula has to be within NEC guidlines. Using Article 220. Please simplify the formula. I just need to know kw and not kilowatt hours
I can help you if you are more specific.
Can you please put your question again and guive more details what you want to do?
Best Regards
AvraamG