SE vs Romex Wire

[Bama_Electrical]

Was having a conversation with a couple of electrician buddies about wire and they got to arguing about the type wire each other uses to feed an interior sub panel off of other interior sub panels. One of them is using 2 AWG Romex to run an 80 amp sub panel, but was told he should be using SE cable for that. Was curious what y’all thought.

 

[infinity]

Either one. Not sure why someone would say to use one over the other except maybe for the cost difference.

 

[Dennis Alwon]

Not sure I have seen nm in aluminum that large. I remember in the old days buying #2/3 copper NM -- . A friend of mine said he still has a copper 3/0 piece of se cable. He'll never use it-- I told him he could probably scrap it and get more than he paid for it.

 

[augie47]

A lot of our HVAC guys switched from NM to SE to take advantage of the 75° rating.

 

[infinity]

A lot of our HVAC guys switched from NM to SE to take advantage of the 75° rating.

Excellent point.

With the two types of cables in the same size and material the SE can yield a higher ampacity.

 

[electrofelon]

Was having a conversation with a couple of electrician buddies about wire and they got to arguing about the type wire each other uses to feed an interior sub panel off of other interior sub panels. One of them is using 2 AWG Romex to run an 80 amp sub panel, but was told he should be using SE cable for that. Was curious what y’all thought.

SE cable all the way. I just about never use NM over #8, hate the stuff- crappy ampacity due to 60 degree restriction, expensive, heavy....

 

[kwired]

SE cable all the way. I just about never use NM over #8, hate the stuff- crappy ampacity due to 60 degree restriction, expensive, heavy....

I use #6 NM cable, but somewhat limited. Running to a air handler with 9.6 kW heat and across the building, chances of using NM cable go up.

Run same sort of circuit to air handler in same mechanical room the panel is in and the chance of using a raceway method is much greater.

 

[LarryFine]

I use #6 NM cable, but somewhat limited. Running to a air handler with 9.6 kW heat and across the building, chances of using NM cable go up.

The longer the run, the greater the odds I'll be using aluminum SE or SER.

 

[kwired]

The longer the run, the greater the odds I'll be using aluminum SE or SER.

#6 is sort of largest copper I will run in most cases. But then length of run will factor into it. Most of time it is outdoor underground runs where I will be debating whether to use 6 copper or 4 aluminum, but then PVC went up and a jump in raceway size is a bigger factor than it used to be as well.

 

[LarryFine]

For loads like hot tubs that require copper, the disconnect is a great place to transition to it from aluminum.

 

[jimport]

#6 is sort of largest copper I will run in most cases. But then length of run will factor into it. Most of time it is outdoor underground runs where I will be debating whether to use 6 copper or 4 aluminum, but then PVC went up and a jump in raceway size is a bigger factor than it used to be as well.

With the price of copper you can run #2 AL, get more amps for less cost.

 

[LarryFine]

With the price of copper you can run #2 AL, get more amps for less cost.

Absolutely! That's what I've been using for generators, car chargers, etc. (not always #2)

 

[HuntNJ]

I use type mc cheaper and easier to use if going the copper route in my opinion, Bought 6/3 mc the other day for a oven and it was cheaper than the 6/3 romex.

 

[kwired]

I use type mc cheaper and easier to use if going the copper route in my opinion, Bought 6/3 mc the other day for a oven and it was cheaper than the 6/3 romex.

That kind of been the case since plastics (used in sheath) went sky high in price. Even 12-2 MC close to price of NM at one time, not sure about now. But still less labor and other items needed for NM making it still the lesser cost overall if you have choice of what to run.

 

[infinity]

That kind of been the case since plastics (used in sheath) went sky high in price. Even 12-2 MC close to price of NM at one time, not sure about now. But still less labor and other items needed for NM making it still the lesser cost overall if you have choice of what to run.

On my current job which is a 62 story building we've been using MC cable for temp light and power. It's cheaper and sometimes easier to get than NM cable. One added benefit is that it can be cut off and left abandoned in place when you're done while NM cable has to be removed.

 

[electrofelon]

I use type mc cheaper and easier to use if going the copper route in my opinion, Bought 6/3 mc the other day for a oven and it was cheaper than the 6/3 romex.

I use AL MC a lot for my commercial stuff. Got a 400A feeder with 2 sets of 250-4, and even much smaller stuff too: I've got one coming up that is #4 AL MC for a 65/70A feeder.

 

[ritelec]

A lot of our HVAC guys switched from NM to SE to take advantage of the 75° rating.

Excellent point.

With the two types of cables in the same size and material the SE can yield a higher ampacity.

I'm still one for copper and intead of working with larger wire and lug size limitations I will pass the extra cost to the customer for the copper. But, please confirm, does 338.10(B)(4) limit it's rating to 60 degree ONLY if it's in insulation? Other than that the 75 degree c. rating applies?
Thank you.

 

[ritelec]

I'm still one for copper and intsead of working with larger wire and lug size limitations I will pass the extra cost to the customer for the copper. But, please confirm, does 338.10(B)(4) limit it's rating to 60 degree ONLY if it's in insulation? Other than that the 75 degree c. rating applies?
Thank you.

scrub this... thank you.

 

[LarryFine]

For informed customers, or those who ask, I will price the work using each conductor type.

 

[garbo]

Excellent point.

With the two types of cables in the same size and material the SE can yield a higher ampacity.

Always thought that copper NM cable even at 60 rating had a higher ampacity then same size SE Aluminum cable. Do not know or want to know how much #2 NM cable cost. Last week a 250' coil of 12/2 NM was $259. Over a buck a foot. WOW. So now a days would only use aluminum SE cable. Besides enomous cost saving easier to handle.