6/3 nm cable for stove

[Jpflex]

How do you properly adjust ampacity for 6/3 Romex cable for a stove? For ambient temperature correction, NEC says to use table 400.4 (A) (1) for cables and cords but there is no listing for “NM” cable in either cable/ cord table

The table says the #6/3 cord is good for 45 amperes with an ambient temperature of 85 degrees celcius but if higher to derate according to table 310.15 (B) 1 which depends on the cable insulation rated temperature and ambient temperature but there is no listing for NM cable or it’s insulation temperature in table 400.5 A or B or the product itself?

Once I figure this out I can find size the branch circuit breaker

 

[Dsg319]

What scenario are you in that you have to make temp adjustments for this stove circuit? Or just curious?

 

[curt swartz]

NM Cable is NOT a Flexible Cord or Cable. It is a Chapter 3 wiring method. It is covered by Article 334.

 

[Jpflex]

NM Cable is NOT a Flexible Cord or Cable. It is a Chapter 3 wiring method. It is covered by Article 334.

I’ll check that but as far as I know NM has been referred to cable because of its outer jacket

 

[Jpflex]

I’ll check that but as far as I know NM has been referred to cable because of its outer jacket

I want to determine the ampacity of the NM “cable” and make sure the ampacity is consistent after temperature correction

 

[Little Bill]

I want to determine the ampacity of the NM “cable” and make sure the ampacity is consistent after temperature correction

Where is this stove being located?

 

[ActionDave]

I’ll check that but as far as I know NM has been referred to cable because of its outer jacket

It's a chapter 3 wiring method though, so you won't find it 400.4

 

[wwhitney]

I’ll check that but as far as I know NM has been referred to cable because of its outer jacket

Yes, it's a cable, but it's not a "flexible cable". Try comparing 6/3 NM's bendability to 6/3 cord, and you'll agree. Article 400 does not apply.

Cheers, Wayne

 

[Jpflex]

I’ll check that but as far as I know NM has been referred to cable because of its outer jacket

I want to determine the ampacity of the NM “cable” and make sure the ampacity is consistent after temperature correction

 

[Jpflex]

Yes, it's a cable, but it's not a "flexible cable". Try comparing 6/3 NM's bendability to 6/3 cord, and you'll agree. Article 400 does not apply.

Cheers, Wayne

Ok

 

[infinity]

I want to determine the ampacity of the NM “cable” and make sure the ampacity is consistent after temperature correction

What is the ambient temperature that the cable will be run in and what size branch circuit are you using?

 

[tom baker]

It would unlikely that temp adjustment is required for a single NM cable, but that adjustment is from the 90 dg C rating but the final ampacity is based on the 60 deg c rating

 

[tthh]

As I recall, the non-derated ambient temperate limit is 30C (86F). So, if you are installing in a house, I don't see any issues.

 

[Jpflex]

As I recall, the non-derated ambient temperate limit is 30C (86F). So, if you are installing in a house, I don't see any issues.

What does this mean? If your in an area whether indoors or outdoors, where ambient temperature exceeds 85 degrees celcius then why wouldn’t you derate according to 310.15

 

[letgomywago]

What does this mean? If your in an area whether indoors or outdoors, where ambient temperature exceeds 85 degrees celcius then why wouldn’t you derate according to 310.15

The insulation on nm is 90°c but code only allows sizing it in the 60°c column. This covers just about any situation it could be in in North America that could be a concern for derating or running through thermal insulation.

 

[retirede]

What does this mean? If your in an area whether indoors or outdoors, where ambient temperature exceeds 85 degrees celcius then why wouldn’t you derate according to 310.15

Where are you installing NM that the ambient is 85 C? That’s 185 F!

 

[letgomywago]

To make it simple 6-3 romex would get a 50 amp breaker for a range with a 50 amp receptacle. A subpanel ran with 6-3 romex could be either a 50 or 60 amp overcurrent protection so long as the load calc is 55 amps or less using next breaker size rule.

 

[Jpflex]

Where are you installing NM that the ambient is 85 C? That’s 185 F!

The NEC table 310.15 B shows 86 degrees F not C, typo correction now made. Since the ambient temperature in my area according to copper.net is 100 degrees F a derating of 0.91 x conductor ampacity (for a 90 degree rated conductor = new ampacity of NM cable

 

[infinity]

The NEC table 310.15 B shows 86 degrees F not C, typo correction now made. Since the ambient temperature in my area according to copper.net is 100 degrees F a derating of 0.91 x conductor ampacity (for a 90 degree rated conductor = new ampacity of NM cable

And that ampacity still exceeds the 60° C rating of #6 NM cable so for all intents and purposes you can ignore the derating.

 

[Jpflex]

And that ampacity still exceeds the 60° C rating of #6 NM cable so for all intents and purposes you can ignore the derating.

Ok but I haven’t seen a table that list nm cable in its list of inclusive conductors to determine the ampere rating of nm cables for an ampacity at 60 degrees celcius

I will look up chapter 3 wiring method section of NEC as soon as I get a chance though