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Posted By: ngoody24 need help - 10/22/05 06:31 PM
Hi everone. I have a question i need to know if im on the right track on or not.

ok here we go

one cooktop and two ovens are connected to one brach circuit in a kitchen ofa one family dwelling. The cooktops name plate rating is 4kw@240volt , while each oven has a nameplate of 5.5kw@240volt. The min load calculation for this brach circuit is _____watts.


I think the answer that I found in the (1993) code book is table 220-19.
answer is 14kw
according to the table 3 appliances = 14kw
any help would be grateful thanks..
Posted By: caselec Re: need help - 10/22/05 07:53 PM
a single cooktop and not more than 2 ovens connected to a single branch circuit is considered a single range not 3 ranges. Look at the notes under the table but I believe you add 5% for each kw over the 12kw rating.

Curt
Posted By: ngoody24 Re: need help - 10/22/05 08:43 PM
Just got done reading the note #1
ok lets see
4kw(rating of above)+5.5kw(rating of above)+5.5kw(rating as above)=15kw-12kw(per note 1)=3kw+5%=3.15kw+12kw=15.15kw
15.5kw min is this right?
Posted By: jw electric Re: need help - 10/22/05 11:01 PM
Note 4 Branch-Circuit Load. It shall be permissible to calculate the branch-circuit load for one range in accordance with Table 220.55. The branch-circuit load for one wall-mounted oven or one counter-mounted cooking unit shall be the nameplate rating of the appliance. The branch-circuit load for a counter-mounted cooking unit and not more than two wall-mounted ovens, all supplied from a single branch circuit and located in the same room, shall be calculated by adding the nameplate rating of the individual appliances and treating this total as equivalent to one range.

5.5+5.5+4= 15
15 ā€“ 12 = 3
3 X 5% = 15%
Demand in column ā€œCā€ is 8, 8 X 115% = 9.2
The demand for these three cooking appliances will be 9,200va
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