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#### FlyingSparks

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Okay, here is the scenario my instructor laid out in a recent question on a test we had. I've been doubting my work ever since I took the test for some reason.

You have a 120/240v 6kw cooktop and a 120/240v 8kw oven, determine the amount of branch circuits needed, conductor sizes, ocpds, and the load in volt amperes for each circuit.

Okay so,
I remembered that somewhere in the NEC it allows you to combine both on to one circuit -- I think, so here's what I calculated:
8 kW + 6kW = 14 kW
14 - 12 = 2 kW
2 * 5% = 10%
8 * 1.1 = 8.8 kW

So I said one branch circuit, 8awg wire, with an OCPD @ 40amps. Load is 8800va.

Anyone see a problem with the answer I gave? It's been bothering me like crazy.

#### FlyingSparks

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Anyone?

#### aftershockews

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1- 6/3 w/ ground circuit on a 50 amp breaker.

#### bkmichael65

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8kW+(8kW*.10)=8.8kW/240=36.66 amps. #8cu and 40amp cb. Looks good to me

#### Dennis Alwon

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T. 220.55 note 4 is your reference and you are correct. 40 amp cir.

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#### Dennis Alwon

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I have said this before but it always amazes me that you can have a 9 kw range or a 16 kw range and they would both calculate out to 40 amps. 16 kw would be 8kw plus 5% for every kw over 12kw. 16kw is 4kw over 12 kw so .05x4= .2
1.2*8 kw= 9.6kw or 9600. Divide by 240 and you get 40 amps

#### Dennis Alwon

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You are the man....:thumbsup: :laughing:

#### FlyingSparks

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You guys have made my night, I was searching for that reference, forgot it was a note under the table.

What is the rationale behind that Dennis? I still struggle to understand this whole oven load calculating wizardry haha

#### aftershockews

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I am not a code guru. I have always calculated an electric stove or oven, range top at 125% of the namplate wattage. I mean, hell, we have to do it for a water heater and an oven is going to be fired up longer than a water heater especially on Thanksgiving.

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