Romex Wire

[James L]

i talked with 3 inspectors and also the town inspector for the area the job was done in and all the inspectors for my area said 8 is fine to put on a 50 and town codes supersede nec so i guess there are exceptions ... and to note each inspector has stated that years ago they used to put 8 on 50 all the time with no issues.. again i really would like to know if any number 8 has burned up or caused damage to the 50 amp breaker this is not nm like years ago its nm-b ... anyways case closed i really dont have a leg to stand on going up against the town inspector if he allows it

You don't have to answer if you don't want to, and I hope I don't sound accusatory, but I have a few questions which I'm just too curious about.

You said you've run into a few jobs like this. What were you doing there that you were able to run into these violations? Are you a home inspector? That may answer most of my other questions....

How do you happen to notice that something you're not involved with was changed over from NM-B to THHN in EMT? multiple times you've just happened to notic stuff like that?

You mentioned not having a leg to stand on. Why do you need one? Are you trying to pressure the inspectors to retroactively fail the installs?

Like I said I'm just curious.

But on another note, I don't agree with the masses who are ducking for cover over every code violation, looking to see who's coming out of the woodwork with a lawsuit.

The code was/is written by industry experts who likely have less true understanding than a good 25 year electrician. Why can't a seasoned electrician be considered an industry expert? And if he's had a thousand installs with no issues, then why try to stir up a hornet's nest?

 

[shockdudude]

An a/c compressor can be fed with 8 Romex and fused ad 50 amps if minimum circuit ampacity on name plate is 40 or less but requires larger minimum fuse for startup

 

[don_resqcapt19]

You don't have to answer if you don't want to, and I hope I don't sound accusatory, but I have a few questions which I'm just too curious about.

You said you've run into a few jobs like this. What were you doing there that you were able to run into these violations? Are you a home inspector? That may answer most of my other questions....

How do you happen to notice that something you're not involved with was changed over from NM-B to THHN in EMT? multiple times you've just happened to notic stuff like that?

You mentioned not having a leg to stand on. Why do you need one? Are you trying to pressure the inspectors to retroactively fail the installs?

Like I said I'm just curious.

But on another note, I don't agree with the masses who are ducking for cover over every code violation, looking to see who's coming out of the woodwork with a lawsuit.

The code was/is written by industry experts who likely have less true understanding than a good 25 year electrician. Why can't a seasoned electrician be considered an industry expert? And if he's had a thousand installs with no issues, then why try to stir up a hornet's nest?

In general it is written by the code users who submit Public Inputs to make changes. The deadline for submitting a change for the 2026 code is 5pm eastern on the 7th of this month.

 

[Birken Vogt]

Somehow, SER got the NM temperature rating sentence removed from its ampacity. So you can now run equivalent SER per the 90 degree column, if I understand correctly. But NM is still the same as it ever was.

 

[infinity]

Somehow, SER got the NM temperature rating sentence removed from its ampacity. So you can now run equivalent SER per the 90 degree column, if I understand correctly. But NM is still the same as it ever was.

SER would be limited to the 75°C ampacity due to the temperature ratings of the terminations.

 

[Birken Vogt]

SER would be limited to the 75°C ampacity due to the temperature ratings of the terminations.

Granted, but otherwise the peculiar limitations of NM do not apply any more, even if it is "installed as NM" like the code used to say.

Any idea why that is?

 

[kwired]

from my original post i stated that its romex to a certain point then its thhn and emt the inspector for the area says this is fine in the old days the master electricians would always put nm 8 on 50 amp breakers so i need more of a clarification as why this is a violation before i challenge anyone on this.. in all your years as a electrician have you seen number 8 romex burn up on a 50 amp breaker

They maybe did that but I don't believe it was ever NEC compliant other than for the mentioned AC units with a MCA of no more than 40.

Most common place to see 8 AWG in past was for cooking appliances. By nature they usually have low enough demand that they aren't going to overheat conductor insulation. Something that has more of a continuous demand possibly could though

 

[nizak]

They maybe did that but I don't believe it was ever NEC compliant other than for the mentioned AC units with a MCA of no more than 40.

Most common place to see 8 AWG in past was for cooking appliances. By nature they usually have low enough demand that they aren't going to overheat conductor insulation. Something that has more of a continuous demand possibly could though

#6 NM cable on a 60 amp breaker is another scenario that’s widely interpreted by inspectors.

55amps, next size up breaker. blah blah blah…

 

[infinity]

#6 NM cable on a 60 amp breaker is another scenario that’s widely interpreted by inspectors.

55amps, next size up breaker. blah blah blah…

Not sure, are you saying that it is or isn't permitted? That rule is black and white so there is no gray left open to interpretation.

 

[nizak]

Not sure, are you saying that it is or isn't permitted? That rule is black and white so there is no gray left open to interpretation.

Several inspectors locally say it’s compliant.
60 degree column is 55A and they allow the next standard OC size which is 60A.

Many 48 A vehicle chargers around here wired with 6/2 NM cable

 

[kwired]

Several inspectors locally say it’s compliant.
60 degree column is 55A and they allow the next standard OC size which is 60A.

Many 48 A vehicle chargers around here wired with 6/2 NM cable

Which I'm pretty certain they are to be considered continuous loads, that puts you at minimum conductor ampacity of 60 and #6 @60C is only rated 55 amps. If one uses cable/conductors with a 75C rating 6 AWG would be acceptable.

 

[infinity]

Many 48 A vehicle chargers around here wired with 6/2 NM cable

That is not code compliant when you need a conductor with a minimum ampacity of 60 amps.

 

[nizak]

That is not code compliant when you need a conductor with a minimum ampacity of 60 amps.

My point.

There are numerous items throughout the code that are mis interpreted by inspectors.

I’m not getting down on anyone just saying that even “black and white” as you refer to it as is neither understood or enforced by many AHJ’s

Surprisingly I believe very little bad ever comes from the allowances that are made in error during inspections.

Leads one to believe that there is a lot of forgiveness in the way the code is laid out.

Things done wrong are still safe enough to withstand the load or burden put on them.

Just my opinion.

 

[shockdudude]

all wire is already rated for 100% continuous loads, hence 60 amp breaker for for 125% of 48 amps for any continuous load on any wire rated for 50 amps...If you could buy a 55 amp breaker this exception would be void..talking about 6 romex

 

[nizak]

Going online one can find where people have set extreme conditions to test different types of wiring.

One I recall was 14/2 NM starting with a load of 15 amps and increasing gradually.

If I recall, total failure came at close to 100 amps.

My experience has been over the years that with NM for instance the termination points fail far sooner than the conductor.

 

[shockdudude]

Yes the 50 amp car charger using a range receptacle for continuous loads should be illegal, and I personally only use hardwire connections and Polaris termination blocks when changing from romex to thhn at this draw not wire nuts or wago's

 

[letgomywago]

Yes the 50 amp car charger using a range receptacle for continuous loads should be illegal, and I personally only use hardwire connections and Polaris termination blocks when changing from romex to thhn at this draw not wire nuts or wago's

I like OG split bolts at that point or even splice reducers. Polaris connectors I feel are over priced for what they are and I can do a split bolt in about 2 or 3 min so that's a savings of 15 bucks for 6 bucks in labor and they have better ranges and smaller volume taken up. Splice reducers take the same space though but I can do those in 1 minute and their range of conductors are huge.

 

[retirede]

all wire is already rated for 100% continuous loads, hence 60 amp breaker for for 125% of 48 amps for any continuous load on any wire rated for 50 amps...If you could buy a 55 amp breaker this exception would be void..talking about 6 romex

The way the NEC is written, a 48A continuous load wired with #6 NM on a 60A breaker is a violation. That’s not even debatable.

 

[letgomywago]

The way the NEC is written, a 48A continuous load wired with #6 NM on a 60A breaker is a violation. That’s not even debatable.

At this point I tend to go to SE cable it's quick and simple and solves the issues. It's wet rated also so if it's a charger going outside all is well if sleeved correctly.

 

[Fred B]

At this point I tend to go to SE cable it's quick and simple and solves the issues. It's wet rated also so if it's a charger going outside all is well if sleeved correctly.

Can you even get copper SE? Supply houses around me claim it's not available. Every EV charger I've installed indicate CU conductor only.