DIYbanter - View Single Post - electrical questions

wrote:
This is what I got from the NEC handbook 2005 (Article 220, table
220.55):

"..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."

The handbook also explains (has a picture 210.21) how to pick tap
conductors when installing oven and cooktop on the same circuit under
210.19(A)(3) Exception No. 1.

Table 220.55 lists the max demand for a 12KW range as 8kW (derating it
assuming the range is not used to its full capacity).

The handbook has an example that shows how to get a combined rating for
multiple appliances. In my case, the cooktop is rated at 9.6kW, and the
oven is at 7.2kW. According to their formula, my combined maximum load
is 10.4kW which requires 43.3 amps.

Is anybody familiar with all this? According to this rule, shouldn't I
be able connect the cooktop and the oven to the same circuit (60 amp)?

Thanks.
Matt

Yes, I would agree with your summary.

Note that the branch circuit is limited to a max of 50 Amp rating,
so you would replace the 60A breaker with a 50A unit.

On a side note, if the raceway will be used as the equip ground
(raceway does not contain a grounding conductor), I would
verify the integrity of the raceway connections (fittings)
to perform as an effective grounding means.
Jim