Some electrical code questions...

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Externet

Joined Nov 29, 2005
2,223
Hello. Some curiosity...

- Can UF-B cable be run inside a dwelling attic, walls, basement without conduit ? Can it be run on surface of exterior walls ?

1621880491576.png

- Can plastic conduit be installed inside a dwelling with 'Romex' type of cable in it ?

- Why is this called 'solid' ? ---->https://www.nassaunationalcable.com...MIna7R7fXi8AIV7waICR3HBQzcEAQYASABEgIriPD_BwE

- The ground conductor, which is not meant to carry current; can it be smaller gauge ?

1621880582377.png

- Can a bare conductor in a red + black + bare, cable be used as neutral if covered by a white sleeve at both ends ?

https://www.allaboutcircuits.com/textbook/reference/chpt-2/wiring-color-codes/
 

MaxHeadRoom

Joined Jul 18, 2013
28,698
Hello. Some curiosity...

- Can UF-B cable be run inside a dwelling attic, walls, basement without conduit ? Can it be run on surface of exterior walls ?

View attachment 239484

- Can plastic conduit be installed inside a dwelling with 'Romex' type of cable in it ?

- Why is this called 'solid' ? ---->https://www.nassaunationalcable.com...MIna7R7fXi8AIV7waICR3HBQzcEAQYASABEgIriPD_BwE

- The ground conductor, which is not meant to carry current; can it be smaller gauge ?

View attachment 239486

- Can a bare conductor in a red + black + bare, cable be used as neutral if covered by a white sleeve at both ends ?
UF-B cable should not really be ran concealed.
I think they just use a handy pic when solid was meant to be intended?
Ground conductor should ideally be the same size as all conductors.
You could run Romex that way, but why?
If you run conduit it would pay to run THHN/TEW/MTW etc.
You cannot use a bare conductor for neutral.

EDIT:
UF-B can be used buried in solid conduit.
 
Last edited:

Lo_volt

Joined Apr 3, 2014
317
- Can plastic conduit be installed inside a dwelling with 'Romex' type of cable in it ?
You could run Romex that way, but why?
The only place you definitely don't want to run Romex in conduit is where there is a possibility that water could infiltrate the conduit, e.g. underground or outside. This is because Romex has paper separators between the conductors. If that paper gets wet it will reduce the dielectric separation between the conductors, reducing the effective voltage rating of the cable.

If you do put Romex inside of conduit you may need to oversize the conduit as Romex is specified for temperature in free air not in conduit. Thermal damage to the insulation may occur if the wire runs full current through it for extended periods.

Peeling the outer jacket off of Romex does not make it THHN or THWN.

If you want to minimize the amount of THWN that you buy, you can bring it into a junction box in the house in conduit and splice it to Romex once it's inside. Always remember that junction boxes like that need to be accessible.

My solar inverter is in a detached garage. I had an electrician do the AC wiring for it. He used #2 AWG copper in conduit between the two buildings (upgraded my garage power, now I can run any tools that I want!). Inside the house he used SER #2 aluminum to the breaker panel. This was to keep cost down as aluminum is cheaper than copper. It also allowed him to weave the SER through joists and walls to the panel. SER is vinyl jacketed similar to Romex. With it there was no need for conduit inside the house.
 
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