Another 2 prong electrical question
#1
10-18-15, 12:42 PM
Another 2 prong electrical question
Greetings all,
Sorry if this subject is beat to the death, but I am another one of those "halp me 2 prong plugs" people.
My understanding is that to properly go from 2 prong to 3 prong, I need to either run new wiring, or use GFCI with a "no equipment ground" sticker. I just want to make sure I don't have an option 3 I'm not aware of. I've seen a clip that hooks to the metal box, but I'm under the impression those won't cut it.
Thanks for the help. I've been doing a lot of reading on electrical lately and find it to be quite interesting.
Cheers
Sorry if this subject is beat to the death, but I am another one of those "halp me 2 prong plugs" people.
My understanding is that to properly go from 2 prong to 3 prong, I need to either run new wiring, or use GFCI with a "no equipment ground" sticker. I just want to make sure I don't have an option 3 I'm not aware of. I've seen a clip that hooks to the metal box, but I'm under the impression those won't cut it.
Thanks for the help. I've been doing a lot of reading on electrical lately and find it to be quite interesting.
Cheers
#2
10-18-15, 12:46 PM
Group Moderator
You would need to determine what type of cabling your house uses for a third option.
If it is two wire NM (romex) with no ground.... no third option.
If it is BX (metal clad) cable with the internal bare ground wire then you can add a jumper wire from the box to the device.
If you do have the BX.... go to where it's connected at the panel. Look outside where it goes into a connector. Do you see a little silver wire wrapped around the metal armor ?
If it is two wire NM (romex) with no ground.... no third option.
If it is BX (metal clad) cable with the internal bare ground wire then you can add a jumper wire from the box to the device.
If you do have the BX.... go to where it's connected at the panel. Look outside where it goes into a connector. Do you see a little silver wire wrapped around the metal armor ?
#5
10-18-15, 03:56 PM
I didn't see anything that looked like BX running back to the breaker box. It's definitely older cable (1900s house) and I haven't found anything that looks like ground conductor with any of the switches so far.
#6
10-18-15, 04:04 PM
It's definitely older cable (1900s house) and I haven't found anything that looks like ground conductor with any of the switches
#8
10-18-15, 05:48 PM
You do have another option. You can run a separate ground wire from the receptacle in question to the panel with the breaker for that branch circuit. The separate ground wire may follow the circuit conductors exactly, approximately, or vaguely. Should this separate ground wire first reach a fat ground wire (grounding electrode conductor) leaving the panel for a ground rod or water pipe, it may end and be clamped on there.
As I interpret the code, the separate ground wire may daisy chain through or have taps to additional receptacles on the same branch circuit.
You may not extend the branch circuit given a ground in this fashion (or not given a ground).
As I interpret the code, the separate ground wire may daisy chain through or have taps to additional receptacles on the same branch circuit.
You may not extend the branch circuit given a ground in this fashion (or not given a ground).
#10
10-18-15, 06:34 PM
Group Moderator
1900's house..... so..... what is the year the house was built ?
It could almost be knob and tube. If not....maybe cloth covered.
It could almost be knob and tube. If not....maybe cloth covered.
#12
10-18-15, 06:46 PM
Group Moderator
Ok.... so that would be cloth covered jacket and possibly cloth covered rubber insulation on the wiring. Very brittle to work with and the insulation crumbles easily. Work carefully with it.
No ground.
No ground.
#13
10-18-15, 06:52 PM
it seem to be cloth over rubber. Looked to be copper at least. It was definitely not fun stuff to work with at all since they don't leave any extra. The receptacle attached to some new wiring took me mere minutes to change. The 4 switches took me probably over an hour due to having no slack.
#15
10-18-15, 07:03 PM
Definitely agree that there's probably been some level of rewire. I have a mix of various vintage wire here; it's kinda like a museum, lol. Some of it is nice "new" romex. Other is icky sticky cloth stuff.
Heck for all I know there was no electrical in this home when it was first built. I'm fairly sure there wasn't a bathroom. lol. The bathroom is literally like a closet.
Heck for all I know there was no electrical in this home when it was first built. I'm fairly sure there wasn't a bathroom. lol. The bathroom is literally like a closet.
#16
10-18-15, 07:17 PM
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 16,321
Received 38 Upvotes
on
30 Posts
Some pictures of the wires and cables would help to identify the age. Rubber insulation with cotton or linen over braid on individual conductors would tend to denote knob & tube wiring and that could be from the earliest addition of electricity to the house. Rubber insulation on copper wires has a tendency to corrode the copper so it was common to have the copper "tinned" (thin coating of tin) before the insulation was added. Plastic insulated conductors in a "cloth-covered" over braid would denote the earlier form of type NM cable, probably from the late 1940s through the 1970s.
It MAY be far easier, and definitely better, to simply pull new type NM cable to new three-prong (grounding) receptacles than to attempt to run separate equipment grounding conductors.
It MAY be far easier, and definitely better, to simply pull new type NM cable to new three-prong (grounding) receptacles than to attempt to run separate equipment grounding conductors.
#17
10-18-15, 07:28 PM
Thx Furd. I think you also posted on my thread about my garage. In talking w/ the Mrs we're both thinking about the idea of running new. Most of the upstairs stuff seems to be ok, and I have af ull basement to access isn't too terrible.
There's so much janky electrical work going on in this place that to make things make more sense it would be worth doing. The bathroom, portions of the kitchen, the Mudroom and another part of the house are all on one breaker. Another portion of the kitchen is on a separate breaker, etc etc.
There's so much janky electrical work going on in this place that to make things make more sense it would be worth doing. The bathroom, portions of the kitchen, the Mudroom and another part of the house are all on one breaker. Another portion of the kitchen is on a separate breaker, etc etc.
#18
10-19-15, 06:41 AM
I'll throw my hat into the ring with a comment that it doesn't really matter if he wiring is 80 years old or 110 years old. It's functionally obsolete and far beyond its safe, useful service life. I would look to abandon and replace the existing wiring rather than upgrade and retrofit it in place. A couple spools of Romex isn't all that expensive.
#19
10-19-15, 11:33 AM
Group Moderator
A couple spools of Romex isn't all that expensive.
#20
10-19-15, 12:36 PM
Oh I get it, but as a DIY project it can be done over the course of a year. I'd rather spend my time doing the full rewire than 70% of the work fishing retrofit ground wires and gaining nothing but equipment ground. With the understanding of course that there may be a light box or switch look here and there that can't practically be replaced without wrecking the plaster work. AFCI breakers and proper grounding all around those remaining segments will go a long way to improving safety of the system.
#21
10-21-15, 05:43 PM
I looked at a 1000 ft spool of 12/2 at lowes yesterday and it was only like 200 dollars. That to me isn't too bad at all. Like stated above, it's more about replacing it all without having to tear everyhing apart (We stupidly already did some drywall on the living room. The rest of the house is panel/lathe/plaster so not as big of a deal).
#23
10-21-15, 07:42 PM
that's what I was reading is that regular circuits are usually 14-2, while bathrooms and kitchens are usually 12-2 to accommodate 20amps. Would there be any harm in just using 12-2 throughout the house? I figured if 12-2 is 200 for 1000ft, 14-2 must be less 
#25
10-22-15, 03:35 PM
Member
I looked at a 1000 ft spool of 12/2 at lowes yesterday and it was only like 200 dollars.
#26
10-22-15, 03:46 PM
You'll quickly regret purchasing 1000 foot spools. The cost per foot is the same when purchasing 250 foot rolls and the rolls are much easier to handle and work with.
#27
10-22-15, 04:01 PM
Member
I just price checked and it looks like about a 4 dollar difference between a full 1000ft spool and 4 250 ft spools. If tha'ts the price of convenience, I'll pay it, lol.
