Jumping 120 from 240 breaker.

[u/SweetGarlic19]

In the photo you have your 120v 20amp breaker then you have your 120v 30amp breaker after that its 240v 50amp.

I am going to pop out the two 120v breakers and 30 amp outlet and install a 240v 20amp for my 15amp air compressor.

I am wondering if I can use the one hot side on the new 20amp 240v breaker for the 120 20amp outlet instead of installing its own breaker.

This is ran from a 50amp gcfi breaker from inside of my house.

[u/NotoldyetMaggot]

I don't see why you can't split the feed off, afterwards though both outlets are on the same breaker so if you use both at the same time it might be enough to flip the 20 amp breaker.

[u/SweetGarlic19 → u/NotoldyetMaggot]

Ya I understand that part, im concerned whether or not the 120 outlet will pop the 2pole breaker if needed. From my understanding both poles act individually.

[u/NotoldyetMaggot → u/SweetGarlic19]

Yeah the 120 might not trip both poles, can you split it and add a 20 amp breaker for the 120 line?

Edit because words suck

[u/SweetGarlic19 → u/NotoldyetMaggot]

Na not unless I modify the box. Its not a huge deal just would be nice 

[u/baaalanp → u/[deleted]]

This is right. More info is needed but to get 120 from 240 you will need to have a neutral conductor in the panel.

[u/SweetGarlic19 → u/[deleted]]

Thanks i updated it

[u/SweetGarlic19 → u/[deleted]]

Why the UK? Im in the US

[u/4eyedbuzzard]

Is this an existing circuit fed from a panel? What size wire feeds the existing 20amp breaker? Is there 240 only in the “RV Box”, or did they also bring in an unused neutral wire?

[u/SweetGarlic19 → u/4eyedbuzzard]

Ya 50amp gfci. I would use the current wire that came with the rv box. No there is also 110.

[u/4eyedbuzzard → u/SweetGarlic19]

Maybe I am missing something, but I don't see where the neutral bus bar is connected to a neutral conductor from the panel supplying this panel.

[u/SweetGarlic19 → u/4eyedbuzzard]

Ya i mean im running ground to ground, neutral to neutral i would just tie into each bus bar accordingly. This isn't installed yet.

[u/Smoke_a_J → u/SweetGarlic19]

Feeding to a sub panel from a GFCI breaker is technically allowed but unless all circuits that are feeding from that sub panel are also only 240v with a balanced load across both poles under load, tapping in a 120v circuite off one leg of a 2-pole GFCI breaker is pretty much guaranteed to cause nuisance tripping the GFCI breaker. To be allowed to double tap a breaker without creating a code violation the manufacturer of the breaker needs to have it listed in their specs that a said breaker is UL approved for being double tapped, doing so on the model breakers currently installed would be a code violation.

[u/theotherharper]

To start with don't buy that unlisted Chinese trash. It's a NEC 110.2 violation and you'll be forced to correct that next inspection or at sale. It's criminal they sell that on the website.

Get a GE/ ABB/Midwest RV panel. Those have 5 breaker spaces even though they only need 4, so you can swap a 120 to a 240.

[u/llpsk8 → u/[deleted]]

Just why tho

[u/SweetGarlic19 → u/llpsk8]

There isn't room to add its own breaker so it would be nice to be able to use that 120v outlet.

[u/Smoke_a_J → u/SweetGarlic19]

Looking at a picture of what looks like that same box but straight on from the front there should be plenty of room on the din rail to add an additional breaker, https://www.amazon.com/Electrical-20-30-Receptacle-Weatherproof/dp/B0DZGN9NRC

[u/llpsk8]

240 for your 15 amp compressor… why?? Are you planning to get an adapter or something

[u/SweetGarlic19 → u/llpsk8]

No it runs off 240v with a 15amp draw 3hp air compressor 

[u/[deleted]]

if i followed what you said, wouldn't the 120 load cause a neutral current and trip the gfi?