Running a Separate Neutral Wire

[tofuguy]

My current eBIAB setup is connected to a 3-wire 240VAC 30AMP service. I would power my pump off a separate 120VAC outlet. I am now upgrading my (Cheap) junction box panel to the following Auber Kit. I will need to upgrade my service to a 4-wire configuration by running a neutral wire from my panel and change the outlet. Question I had, what gauge wire can I get away with for this neutral wire? I have to do nearly a 75 foot run, so trying to understand my options. Also any recommendations of which wire to use (link to buy) will be appreciated. Thank you!

 

[hunter306]

Realistic answer?

Pull the right wire for 30amps/240v at 75ft. That'd be 10/3 Romex Copper (8 if you wanna go aluminum). Is the circuit already a GFCI 30a Breaker? If not, that'd be my recommendation too.

https://www.lowes.com/pd/Southwire-Romex-SIMpull-100-ft-10-3-Non-Metallic-Wire-By-the-Roll/3138981

 

[tofuguy]

I already have a 8/2 run to a 30Amp GFCI Breaker. Seeing if I can salvage that run.

 

[itsnotrequired]

is that existing 8/2 run copper or aluminum? is it nm (romex) cable? how is it presently installed (e.g. routed through wood studs, in a conduit, etc.)? is the existing run exposed/accessible or buried behind drywall/some other finish?

 

[tofuguy]

is that existing 8/2 run copper or aluminum? Aluminum

is it nm (romex) cable? Yes

how is it presently installed (e.g. routed through wood studs, in a conduit, etc.)? Routed in an exposed (painted black) ceiling in the basement, then routed into a wall (5 feet) to the outlet.

is the existing run exposed/accessible or buried behind drywall/some other finish? See above, only finishing is the wall and the painted exposed ceiling in the basement.

One option I had thought of was to run a black wire (taped white going into the panel and taped white going into the outlet) Then I will have to tape my Romex white wire red both inside the panel, and at the outlet.

 

[fragged]

If agree on running the correct wire (8-3 aluminum or 10-3 copper). Use the existing to run a welder or compressor or something.

If not, then conduit with the same wire you have now (8 awg aluminum) in it.

Given how much those two options suck in your situation, I'd be figuring out how to work my existing 120v outlet into the design (120v cord from your box to the receptacle maybe?).

 

[itsnotrequired]

as far as code is concerned, you cannot run an individual current-carrying conductor like you would run romex. it is a nuance in the code but basically if you want to add a neutral for this application, you would either need to add an additional cable (romex) or place that individual conductor in a non-metallic conduit (or rip out the 8/2 and install 8/3 (or 10/3 if you went copper)). you would need a #8 aluminum or a #10 copper conductor. an aluminum hot and copper neutral may look weird but not a code violation for a single-phase circuit, provide all the terminations are rated for both copper and aluminum.

practically, what you describe to do is fine and is not inherently dangerous, just be aware it doesn't technically meet code. you'll want to run that new conductor as close as you can to the existing cable along the entire run (another code requirement). separating hot and neutral by an appreciable difference can result in additional circuit impedance and increased heating of the conductors. because the neutral will be smaller than a #6, code does not allow it to be taped to indicate a neutral. you'll need to run a conductor with a white/gray outer finish. another code thing but practically, taping a black conductor is not an inherent danger.

you might have trouble finding #8 aluminum so may want to go with #10 copper. if it was me, i would redo with 10/3 copper but it will cost about $60 or so extra for the cable.

 

[tofuguy]

Thank you, this answers all my questions. I will have to think which option I will prefer doing. I was trying to save $100 if possible, without an obvious violation (but remain safe always). I knew there will be issues, so that is why I asked before buying anything.

 

[itsnotrequired]

yep, there are code VIOLATIONS! and then there are code...violations. safety should always be the first order and nothing here is some type of eminent danger.

if you have access to by-the-foot cable, it can be a bit cheaper than buying a 100 ft roll at a big box store.

 

[tofuguy]

Ended up buying the 100ft roll of 10/3 copper on Amazon for ~$115. Versus $50 for 100ft of a 10awg copper wire, decided to take the $65 hit and do it right.