Electrical Wiring in the Home/open ground


QUESTION: I just bought a house and some of the outlets are showing open ground when I changed from to prong to three prong outlets. looking further I noticed some have two sets of wires coming in to the box one set with a ground and one set without. how do I handle this to ground these outlets properly


How old is the house and are the cables going into these boxes "BX" (spiraling metal covering)
and or Romex (plastic covering). Romex will have a separate bare ground wire and "BX" will not.


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QUESTION: The house was built in 1916, it's Romex in parts and black covering in parts


Yes you have what I like to call the "original romex" that does not have a ground wire in it. This particular cable has a thick black outer covering and held by thick staples. Last year I ripped a lot of it out of a house in NJ along with its fore runner "knob and tube" wiring which also lacks a grounding wire.

You can handle the lack of a "grounding means" (wire or metal outer covering) by protecting those circuits with GFI breakers or receptacles which is one of 2 legal ways of doing it. The other way is running a separate "grounding wire" to each metal box in the circuit which could prove to be very time consuming not to mention challenging. The GFI's are probably the way to go with the breaker being the best option because you can protect the circuit right out of the panel. If you have fuses which is a good possibility in a 1916 house in PA, you would have to use a GFI receptacle in a separate box by the panel and intercept that circuit there.

By the way unless you go the more challenging route you will have to remove the "grounding" type receptacle's you put in and reinstall new 2 prong receptacles like the ones you took out. The reason being the presence of a "grounding" type receptacle suggests that there is a "grounding" connection at the box when there is none in reality.

If you can get rid of the black cable all together and rewire so much the better.

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Electrical Wiring in the Home

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Licensed Master Electrician (32 years) 6165B Contractor in Closter New Jersey with 40 years total experience in Residential - Commercial - Industrial work. Emergency Service - General trouble shooting and repair work - ONAN & GENERAC generator installation - Paddle fans - Kitchen & Bath exhaust fans - AC lines - Smoke detectors - Telephone lines - Cable TV lines - Computer network cabling - Exterior lighting - Recessed lighting - Security lighting - (200 - 150 - 100 amp service up grades) - Electric Heat - New circuits - New appliance hook ups - and more ! FREE ESTIMATES 201-358-1552 Fully Insured


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"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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