Single Dwelling Service/Feeder Size NEC 220

Status
Not open for further replies.
C

Caper Electric

Member
Location
Calgary,Alberta, Canada
I have completed calculations for single dwellings in the past in about 30 mins. no problem. This time it took me three days. Why? Because I'm trying to use the NEC 220 for my first time. See, I'm an electrician in Alberta, Canada and I'm working on developing a house for use in the US.
So my question is 'Has there been many changes to the NEC rules 220 for load calculations and neutral calculations in the new edition? I could only get a 2005 edition and I'm hoping that I'm not wasting my time and have to recalculate all over again. I have alot more questions than this but seeing how this is my first post I thought i would keep it short.
Thanks,
Caper Electric
 
Proof read load calculation NEC 220

Proof read load calculation NEC 220

Thanks alot for the list of changes. Looks like rules 220 and such have not been changed. I'm wondering if it is wrong to ask someone to review my calculation, or is that against fourm policy?
I have to submit it to the US depertment of energy for the Solar Decathlon Project that is happening in Washington DC in 2009. We need the Service Load Calculation and the Service Neutral Calculation submitted and I don't know any one to proof read it before I send it by Dec. 16th. Do you know if this is possible? Thanks again for your help.
 
Caper Electric said:
I have completed calculations for single dwellings in the past in about 30 mins. no problem. This time it took me three days. (using) NEC 220 for my first time.
Click to expand...

If it works well for you, could you share your 30-minute alternative to NEC 220?
 
Please proof read service calculation

Please proof read service calculation

The 30 min calculation is the CEC (Canadian Electrical Code)calculations that I do on a regular basis. I would like to post my calculation now and see if you can find ant errors.
Thanks

Lighting, receptacles, and appliance calculated load (NEC 220.82 and [C])

Appliance Power See footnote
General/Basic Load 2700 VA (1) see also NEC 220.82[1]

Small Appliance (kitchen) 3000 VA (2) see also NEC 220.82[2]

Laundry 1500 VA

Dishwasher 1500 VA

Dryer 6000 VA

Range (cooktop) 7600 VA

Wall Oven 3600 VA

Microwave 1400 VA

Refridgerator 900 VA

ERV (energy recovery ventilator) 200 VA

AHU (air handling unit) 5760 VA

Domestic Water Pump 1920 VA

Additional Pumps 2088 VA

Instant Boiler 6400 VA

Total 44568 VA
Demands based on NEC
NEC 220.82 23827.2 VA 10000+(40% x 34568)
NEC 220.82 [C] 4632 VA Heat Pump 100%

Total Service/Feeder Load (NEC 220.82 and [C]) 28459.2 VA

I = VA/E
E = 240 V
(NEC 215.2[A][3] and Table 310.15[6])
118.58 A

Wire size #2 AWG rated @ 125 A (suggested wire size #1)
Footnotes
1900 sq ft x 3 VA
21500 Va X 2


And Netural Calculation


Line to Line Loads 240V (not included)
AHU 5760 VA

Heat Pump 4632 VA

Boiler 6400 VA

Line to Neutral Loads 120V
ERV 200 VA

Dom. Water Pump 1920 VA

Laundry 1500 VA

General/Basic 2700 VA

Small Appliance 3000 VA

Refrigerator 900 VA

Dishwasher 1500 VA

Microwave 1400 VA
Total 13120 VA

120/240V Loads
Range (cooktop) 7600 VA

Oven 3600 VA
Total (NEC 220.61 [1]) 11200 VA


Demands based on NEC
NEC Table 220.55 Col B (cooktop/oven) 7280 VA 11200 x 65%
NEC Table 220.54 (dryer) 6000 VA
Total 13280 VA

Total Unbalanced Load for the 120/240V Loads (NEC 220.61 [1]) 9296 VA 13280 x 70%

Total Service/Feeder Neutral Unbalanced Load (NEC 220.61) 22416VA

I = VA/E
E = 240 V
NEC Table 310.16, 90?C Col 93.4 A
Wire size: #3 AWG rated at 110 A (suggested wire size #1)
 
Status
Not open for further replies.
Top