[dwaun]

I need to run some 6 Gauge THHN wire (240v) through my house attic. Since it needs to be in conduit, I thought I'd use some 1/2 in. Electrical Nonmetallic Tubing (ENT) raceway tubing that I found a local box store. Is there any reason why that wouldn't work? I haven't come across any limits/restrictions, but just want to see if anyone else had any concerns.


Thanks for your input!


Don

 

[jbfan]

How many wires? 1/2 is too small. It needs to be at least 3/4, and depending on the number of wires, maybe 1"
Why can't you run cable?

 

[dwaun]

It's 3 wires. Two conductors and a ground.



I need 60 Amps. It's my understand that 6 Gauge Romex NM wire is only good for 55 Amps.


dwan

 

[Sparkyb60]

3/4" conduit, 2 #6 wires , # 10 green ground

 

[jbfan]

It's 3 wires. Two conductors and a ground.



I need 60 Amps. It's my understand that 6 Gauge Romex NM wire is only good for 55 Amps.


dwan

It is rated for 55 amps, but you can go up to a 60 amp breaker, because they don't make a 55 amp breaker.
What are you feeding?

 

[Let it Snow]

Is this for a Hot Tub?

 

[Kevin_Essiambre]

It is rated for 55 amps, but you can go up to a 60 amp breaker, because they don't make a 55 amp breaker.

What are you feeding?

55 amp breakers ARE made and available for most panels...

Sent from my new phone. Autocorrect may have changed stuff.

 

[CodeMatters]

55 amp breakers ARE made and available for most panels...

Sent from my new phone. Autocorrect may have changed stuff.

But just for the sake of CEC discussion, would you say it'd be

allowed on a 60 based on T13?

 

[jbfan]

55 amp breakers ARE made and available for most panels...

Sent from my new phone. Autocorrect may have changed stuff.

Maybe in Canada, but not in the states.

https://www.fs.fed.us/database/acad/elec/greenbook/3_basicdesigns.pdf

See page 5

 

[Kevin_Essiambre]

But just for the sake of CEC discussion, would you say it'd be

allowed on a 60 based on T13?

I suppose it would. Table 2 says #6 is rated for 55 amps at a termination temperature of 60°. Table 13 would permit it, but I would have to check the associated rules, at table 13 states "for general use where not otherwise specifically provided for."

Sent from my new phone. Autocorrect may have changed stuff.

 

[seharper]

It's 3 wires. Two conductors and a ground.

3/4" of any type conduit will suffice.

I wonder what the last person was thinking, laying it out with no conduit. Can't imagine what possessed

I need 60 Amps. It's my understand that 6 Gauge Romex NM wire is only good for 55 Amps.

True, but irrelevant. NM-B cable is forced to use the 60 degree C thermal rating (55A).

THHN running in conduit can generally run at 75 degrees C (65A). But check the connections. If any of those are rated 60C, you must pigtail with a 75C rated splice (like a MAC Block, a good choice for a 6 AWG splice).

When you are provisioning load, you must respect the thermal limit. So in your case if you need to provision 60A, 55A won't cut it; you must do what's required to qualify for 75C operation.

If no breaker is made at that size, you round up to the next available breaker.