Please confirm range circuit sizing.

[ritelec]

Hello all,

I'm installing a circuit for a range/oven (older townhouse , my thinking is 240v). The numbers are close and has me a bit confused. Reading around in 210.19 , 210.23, and 220.19 but I'm still not coming up with the answer.

Manufacturer range/oven specs are: 120/240 or 120/208.
connected load kw rating @ 240/208 is 13.2kw/9.9kw
amps @ 240/208 is 55/48
recommended circuit breaker is 50a


I picked up 6/3 nm-b (55a) and a 60 amp breaker.
Should I up the wire to 4's and use the 60a? Use the 6's on the 60a, or use the 6's on a 50a?

Thanks for the help,

Rich

 

[Dennis Alwon]

what is your wiring method and is it residential? I see it is nm 50 amp breaker should be fine with 6/3

 

[ritelec]

Thanks for the reply Dennis.

Wiring method... romex, nm.... yes residential..... townhouse.

The 50 amp breaker should be fine with the 6/3. But, should the 50 amp breaker and the 6/3 be good with the 13.2 kw oven?

Thanks again.

 

[ritelec]

By the way, like your icon. You play music? If you do and your ever in Jersey , I've got a small project studio..... give me a buzz.


OK.... back to construction. What size circuit for this oven?

Thanks.

 

[raider1]

Thanks for the reply Dennis.

Wiring method... romex, nm.... yes residential..... townhouse.

The 50 amp breaker should be fine with the 6/3. But, should the 50 amp breaker and the 6/3 be good with the 13.2 kw oven?

Thanks again.

Yes, the 50 amp circuit breaker will be fine with a 13.2 kw oven. Remember that you will never have the full 13.2 kw on at the same time.

Chris

 

[Dennis Alwon]

By the way, like your icon. You play music? If you do and your ever in Jersey , I've got a small project studio..... give me a buzz.
Thanks.

Sorry not a musician. Chris (raider) who responded to you also is a head banging rocker.

As chris said 50 amp cir. is fine. I am not certain but I believe it would not be legal to install a 60 on a 50 amp receptacle outlet. 210.21(B)(3) & 210.23(C)

 

[ritelec]

Thank you.

I figured if there was a problem with any tripping I could put it on the 60 (that next higher breaker rule if the wires rated at 55a). But I was questioning the unit rating at 55a. Did that put me at a larger circuit? I'll put it on the 50a. There is an inspection and quite a bit of cutting for this run so I really don't want to have to go back and do it again. I also don't think it's coming with a chord. I'll be hard wiring it. For grins, the 6's on a 50 are going in but, what is the proper conductor and breaker rating as per "by the book" calculations?

13.2kw @240v @55 amps?

Thanks again!

 

[suemarkp]

First, what exactly is the equipment? A range (oven and cooktop combination), separate oven(s) and a cooktop, or something else?

If it is a range or up to two ovens and a cooktop, you can wire per 220.55 Column 3 and adhering to notes 1 and 4.

This would be: 13.2 KW - 12KW = 1.2 KW.
This rounds to 1 KW which means increase the demand in 220.55 column C by 5%.

Column C is 8 KW. Adding 5% is 8.4 KW
8400 / 240 = 35 amps.

A 40A branch circuit would be permissible for this range. A 50A will be plenty. This is why almost every new house only has a 40A range circuit.

 

[jxofaltrds]

By the way, like your icon.

That is not a piano in front of Dennis that is the NEC!

 

[hurk27]

Thank you.

I figured if there was a problem with any tripping I could put it on the 60 (that next higher breaker rule if the wires rated at 55a). But I was questioning the unit rating at 55a. Did that put me at a larger circuit? I'll put it on the 50a. There is an inspection and quite a bit of cutting for this run so I really don't want to have to go back and do it again. I also don't think it's coming with a chord. I'll be hard wiring it. For grins, the 6's on a 50 are going in but, what is the proper conductor and breaker rating as per "by the book" calculations?

13.2kw @240v @55 amps?

Thanks again!

you might want to take a look at 422.30 and especially 422.33(B)

 

[hurk27]

That is not a piano in front of Dennis that is the NEC!

In brail?:roll:

 

[ritelec]

you might want to take a look at 422.30 and especially 422.33(B)

And 422.16 (B) (3).



Thanks so much guys. I'm feeling much better about this install.

Rock on!

Rich