Investor · Union, NJ · Member since 2011 · 838 posts · 295 votes
Hi guys,
I have an electrical issue/question. I own an older 2 family built in 1932. The outlets are mostly 2 prong and it appears there is no ground wire. My tenant is asking me to change to 3 prong so she could readily plug in things without having to use a 3 to 2 prong adapters.
I am ok with changing to 3 prong outlets but I am thinking about it and if there is only a hot and neutral in the wall is it a good idea to change to 3 prong? Would this create a saftey issue or is it the same situation as it is now with 2 prong and no ground and just more of a convenience b/c she wouldn't need the adapter?
You can install ground fault circuit interrupter GFCI, which will trip if there is a short. In order to be legal, you need to label the GFCIs with NO EQUIPMENT GROUND labels that you can get from the electrical supply store.
You can install ground fault circuit interrupter GFCI, which will trip if there is a short. In order to be legal, you need to label the GFCIs with NO EQUIPMENT GROUND labels that you can get from the electrical supply store.
What Marc Donovan just wrote is correct; to comply with electric code, you have to use a GFCI in order to do this without running 3-conductor wiring. Such receptacles must be labeled as he wrote - usually the GFCI will come with tiny pre-printed labels to use for that purpose.
The $0.99 two prong adapters are less expensive, of course. And some of the power packs that come with small electronic devices are often only two prong to start.
Running a jumper from the ground to the neutral will work in grounding older 2 wire wiring to a newer 3 prong outlet. The neutral goes back to the grounding bus in the panel.
This would have to be done for each outlet. For a rental property I don't know if I would bother though.
Running a jumper from the ground to the neutral will work in grounding older 2 wire wiring to a newer 3 prong outlet. The neutral goes back to the grounding bus in the panel.
This would have to be done for each outlet. For a rental property I don't know if I would bother though.
This wouldn't create an alternate ground. Might as well just put a three prong plug and not connect the ground. Of course, that would be against code even though it would not be any more dangerous than using an adapter except that it gives the illusion of a ground to someone who wouldn't know otherwise.
Be sure that the old house can support it. I lived in an old house once that had 2 prong outlets. I plugged in a space heater once, and it melted the outlet and started smoking. Had I not noticed, it could have caught fire. I also had problems with that house having outlets stop working if I plugged in a hair dryer and toaster at the same time (heat appliances use a lot of electricity).
I'm not an expert here in any way, shape or form, but from what I understand, if you have metal outlet boxes and the wiring in the house supports it (conduit from outlet box back to the panel), you should be able to legally use self-grounding outlets. They ground by having their ground screw in contact with the box (which has an electrical path back to the panel.
At least that's how I understand it...again, I'm definitely not an expert!
I'm not an expert here in any way, shape or form, but from what I understand, if you have metal outlet boxes and the wiring in the house supports it (conduit from outlet box back to the panel), you should be able to legally use self-grounding outlets. They ground by having their ground screw in contact with the box (which has an electrical path back to the panel.
At least that's how I understand it...again, I'm definitely not an expert!
This is what I understand too. the conduit can be that flex pipe stuff too. that stuff was not really used on vintage houses in my area though..
I'm not an expert here in any way, shape or form, but from what I understand, if you have metal outlet boxes and the wiring in the house supports it (conduit from outlet box back to the panel), you should be able to legally use self-grounding outlets. They ground by having their ground screw in contact with the box (which has an electrical path back to the panel.
At least that's how I understand it...again, I'm definitely not an expert!
This is what I understand too. the conduit can be that flex pipe stuff too. that stuff was not really used on vintage houses in my area though..
After all this discussion, I was curious how we were doing this in our second Milwaukee house (built in the 1950s with all ungrounded outlets). I sent my electrician an email and this was his response:
"I'll only be using GFCI receptacles where needed, i.e.kitchen, bathroom, basement, laundry,etc. Every other receptacle in the house is of the self grounding type. We can do this because the house was built using armored cable. The armor being the ground path back to the circuit breaker panel. It is not necessary that the wiring going back to the panel be in pipe, the steel armor is just like steel electrical pipe (EMT)."
Another option would be to run new lines to each room and install surface mount electrical outlets. This is relatively inexpensive and provides adequate power to an older home that usually wasn't designed even close to handle todays electrical needs. This just leaves the lights and a few old outlets i service which is safer as well. Just my thoughts to accomolish a couple goals at a reasonible price.
So it sounds like if the house has armored cabling to the outlets the self grounding outlets would work out well. By armored cabling you are referring to the BX cabling right? THis house does in fact have BX runs as that is what was used back then before being replaced with Romex.
1. i will not put a 3 prong in a rental unless i am re-doing the wire. the inspectors will check that every year.
2. i'd tell her to keep using the adaptors
3. i'd not put a GFI since they are $9 each (3 pack is $27).
4. you can not secure the ground with to the metal box and think it's "grounded". that's false information. the inspector will know it's not "wired correctly".
in my house:
1. i have 3 prongs on wires without ground and never had issue (12 yrs now).
2. I have cut off the "third prong" of the cable whenever i had to. but that's my house, not a rental.
I dont think anyone mentioned that if you do use GFCIs you have to find the FIRST outlet in that circuit to protect everything downstream. Sorry is you knew this already.