Question for the pros about a wiring retrofit

[TWX]

Hey,

So, there used to be a pool here, and there's a subpanel wired with 6ga wire from the main panel (if memory serves), uses two breaker positions on the main. There's also a ground. NO NEUTRAL. If I remember correctly it's in a Romex bundle.

It occurred to me that I could possibly repurpose this wiring for adding lighting and electric to the tuffshed as well as running some more circuits to the basement, which currently only has two circuits for five rooms, including the sewage pump for the bathroom.

There's no Neutral though. Could I have a grounding rod driven near the subpanel and use that for Neutral? Or would I have to pull a 6ga Neutral clear from one end of the house to the other? I might upgrade to a 60A breaker in the main panel so that I can run four 15A circuits (shed, basement 3, basement 4, and sewage pump) if that would be acceptable. It looked like, from what I read, that 6ga is acceptable for 60A service.

The shed is used for storage of garden tools. The worst power demand I could see would be plugging in the electric lawn mower or yard blower, which both should be acceptable on 15A service.

If any of my assumptions are wrong, please correct me.

 

[mrb]

post a picture of the inside of the subpanel.

 

[nehog]

Hey,

So, there used to be a pool here, and there's a subpanel wired with 6ga wire from the main panel (if memory serves), uses two breaker positions on the main. There's also a ground. NO NEUTRAL. If I remember correctly it's in a Romex bundle.

Unusual, but not surprising. I guess the pool equipment (pumps) were 240 volts.

It occurred to me that I could possibly repurpose this wiring for adding lighting and electric to the tuffshed as well as running some more circuits to the basement, which currently only has two circuits for five rooms, including the sewage pump for the bathroom.

There's no Neutral though. Could I have a grounding rod driven near the subpanel and use that for Neutral?

NO! It won't work properly, won't balance as a ground rod (or rods) have too much impedance (resistance) for the power been used.

Or would I have to pull a 6ga Neutral clear from one end of the house to the other?

Probably a choice if you can physically do that. May not meet code however, Romex would not allow a separate neutral conductor.

I might upgrade to a 60A breaker in the main panel so that I can run four 15A circuits (shed, basement 3, basement 4, and sewage pump) if that would be acceptable. It looked like, from what I read, that 6ga is acceptable for 60A service.

What is it now? Remember, the rating of the main breaker is not the sum of the circuit breakers in the box. So a 40 amp circuit would very likely work fine.

The shed is used for storage of garden tools. The worst power demand I could see would be plugging in the electric lawn mower or yard blower, which both should be acceptable on 15A service.

If any of my assumptions are wrong, please correct me.

 

[TWX]

Here's the attached pics...

I couldn't find any writing on the wiring, but it looks to be the same gauge as the 6ga wire I used when I wired my compressor's receptacle.

 

[ishiboo]

Here's the attached pics...

I couldn't find any writing on the wiring, but it looks to be the same gauge as the 6ga wire I used when I wired my compressor's receptacle.

You can install a new box and repurpose one hot wire as a "neutral", so you have a single hot and neutral. You will not be able to have 240 from the box, if your sewage pump requires it.

Where does the ground wire run?

 

[TWX]

Yeah, I was afraid that I would have to lose one leg. Oh well.

The ground goes into the romex bundle; I haven't pulled the panel cover off on the main panel yet, so I don't know for certain that it comes out with the rest of the bundle in the main panel, but I would be surprised if it didn't.

I assume, even though the ground is in the romex bundle, that it is not safe to repurpose it as a neutral.

When the weather cools off and the attic is cooler, I might verify that it's off at the breaker, then put the tone generator on the wiring, to see if I can find where it routes in the attic. It's a thick enough bundle that it might not be stapled down like normal smaller runs are, and if it's not, maybe it's possible to re-run the wiring with a neutral.

If I can gain access to the wiring run, would it be in code to run a neutral right next to the existing wiring, or to physically attach it with zip ties or some other kind of wrapping?

 

[mrb]

no. all conductors of a circuit have to be in the same cable or conduit. you cant add a wire to old romex.

 

[foolishpride]

It appears as though they used Service Entrance Cable to feed the panel, which I'm not sure if it's legal or not. It also appears that they just used 1 slot out of the panel, using a single 120 Volt circuit. That panel would seem pretty much useless, as it only gives you a single 2-pole space for a 240 Volt breaker.

If it were me, I would change the panel, and the wire feeding it. I know it's not what you wanted to hear.

 

[TWX]

My bet is that they wired for the possibility of a heated pool, a hot tub, or both, but only used a regular pool pump, hence the single 120V breaker position.

Wouldn't it be possible, hypothetically, with this subpanel, to run two 240V breakers? One using 2-3, and the other using 4-5? That's not how I intend to use it, just curious.

As for not wanting to hear that, correct, but, that's life. If I use the existing pair of insulated wires, repurposing one of them for Neutral, I assume I should wrap white electrical tape at each end.

I'll have to put the tone generator on it to figure out which one is which at each end.

Would it be at all acceptable to run the new individual Hot to both banks of this existing panel? If not I suppose I could simply not use half of the positions, but if it's not a problem to use both halves as a single bus then that would make it a little easier.

 

[mrb]

thats a really old panel, and probably installed back in the late 60s / early 70s when it was ok to feed a subpanel with SE. im no authority on the subject but it could very well be ok to use this (although I would replace the panel and feeder)

 

[TWX]

Update...

I found a 20A single breaker that I had bought but lost the receipt to and couldn't return without both only store credit and a massive restocking fee. It fits the subpanel, so I can pretty much immediately wire in the circuit for the tuffshed.

The house was built in '79, so the subpanel was probably installed at that time. I figure if I get about fifteen to twenty feet of the liquidtight conduit and the proper fittings I can run some 12ga wire for a light and a couple of 20A capable receptacles. I'll also probably move the lawn timer to this circuit, as it's currently on the same circuit as the bathrooms with a whole lot of EMT from the tie-in to the controller.

I plan to swap the double breaker in the main panel to a single 50A breaker, and to add another single 20A breaker to run a new electrical outlet for more convenient yardwork...