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I have an old 3-fuse subpanel (screw in fuses) that currently has two 15 amp fuses and one 20 amp fuse. I want to replace it with a new breaker panel. There is no ground, only hot and Neutral. I bought an Eaton 125 amp load center and I am planning on adding 2 new dedicated lines.

How do I make up for not having a ground wire and/or do I need the ground? Can I use the wiring currently supplying the fuse panel already there? My service is in an apartment and the panel is 4 buildings away so running a new line would be most difficult.

  • Making up for the lack of a ground usually involves GFCIs as far as I can tell. – RedGrittyBrick Feb 12 '16 at 11:06
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    Can you legally do electrical work in an apartment?? Typically no. ....Also, sounds like a really old installation that really should have a professional look at. It's not like you are the only one at risk if something should go wrong. – Speedy Petey Feb 12 '16 at 12:47
  • If I own the apartment why would I not be legally allowed to do electrical work? – AGar Feb 13 '16 at 5:08
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While the electrical code grandfathers existing installations based on the code at the time of installation, as soon as you start a new installation, you will be required to adhere to the current code. With that in mind, regardless of the difficulty involved, you will be required to run a new line that meets all current requirements (wire type, size, burial depth, etc.) , including a dedicated ground.

If you are lucky, the existing cable is in a conduit, and assuming the new cable will fit (conduit size as required by code), you should be able to pull through a new cable with relative ease.

When in doubt, consulting a licensed electrician is always advisable.

  • See NEC 2014 250.32(B)(1) ex. 1, which allows the existing feeder to be used, as long as a few conditions are met. So if the conductors are the size you want, and are in good condition, there shouldn't be a problem using them. – Tester101 Feb 12 '16 at 17:09
  • Isn't that basically the grandfather clause for existing installations, not an upgrade/new install? Did I misunderstand? – Steven Feb 12 '16 at 18:08
  • Yes it is the "grandfather clause", but it's grandfathering in the feeder which is not being changed. You surely couldn't pull a new 3-wire feeder, but you can use an existing 3-wire feeder. As long as it was installed to meet a previous version of the code, and the other conditions are met. I always recommend pulling a new 4-wire feeder, but it's not necessarily required. – Tester101 Feb 12 '16 at 18:50

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