I just discovered 2 circuits upstairs in my 30’s knob and tube bungalow–updated 200a panel and 12/2 or 14/2 w ground wire mostly–are grounded on the neutral.
Or ‘bootleg grounded’ where there’s a green jumper from the grounding screw on the receptacle to one of the neutral screws.
The grounding conductors are not used, pushed to the back of the boxes.
I believe my options are 1) GFI upstream and pull off all the jumpers
or
2) get a grounding conductor back to the panel from the circuit, pull off all the jumpers and hook up all the grounds.
Right?
Replies
Don't know how to fix it besides rewire.... But the way it is, it sure could kill someone without much trouble.
He did say the ground wires were just tucked away in the back of the box. All he has to do is take off the boot leg, attach the proper ground wire and insure that the grounds in the panel are attached to the ground bar.
~Peter
He also says he has knob & tube wiring ... which does not have a ground. It sounds like he needs to have his place looked at by a real electrician.
Here's my take on the general topic:
First, our lives have changed quite a bit over the past 50 years. We expect so much moer, we have so many appliances that we didn't have back then. The problem is that our homes have been largely unchanged. Those of us living in older homes are faced with inadequatly wired homes.
This often leads to improper 'imrovements.' Such as using romex to add a few receptacles ... and not having that ground wire go anywhere
The second major problem is the effect of property sales - made much worse in our recent flipping madness. DIY "remodelers" stopped at nothing to make 'quick fixes" so they could sell the 'improved' property at a hefty premium.
I have nothing against knob and tube wiring, or fuse boxes, as such. When I see them, however, I know the place is old, and the chances of there being improper work are very high. You can only make so many 'quick fixes' before you have a mess. All you're doing is delaying the inevetable major repair.
Nor is this simple lant on my part; my place was built in 1940, with all that implies. I'm looking at having to remove my drywall, reinsulating and rewiring, then closing it up ... one wall face at a time ... all while the place continues to be occupied. I just don't see any way around it.
For anyone in this position, all I can say is to STOP, think it through, develop a plan. Recognize that your plan will likely require several years to optimize ... prepare to wait that long ... then plan your work. Once you start, work your plan. Just remember that there are no quick fixes.
For your immediate situation, I'd remove every receptacke, add a shallow "wiremold" extension box, and instal a GFCI receptacle. I would not 'feed through' the GFCI, unless I was certain of ALL the connections downstream.
Well said. I'm in a house right now that needs updating. The panel is 100 amps and there isn't one GFI/GFIC in the house or outside.
My wife has her office in one large room with no grounds. She is concerned about her equipment.
I've told her we need a new panel but it just gets put on the back burner. If it still works it doesn't get fixed.
Same with the water heater. It's 12 years old and the piping is a mess.
GFICs are easy to add, 100 amp service is adequate for average houses, and my 5 year water heater is pushing 20, so you aren't too bad off. I did replace my 60 year old gravity furnace a couple years back, but it still worked.
"He also says he has knob & tube wiring ... which does not have a ground. It sounds like he needs to have his place looked at by a real electrician."
Oh ye of little faith! I wired my other house entirely, under permit, with a new service and a subpanel. I'm up to it.
;-)
The only remaining knob and tube runs only overhead lighting off of 12 and 14/2 with ground so I think I'm ok there. I would just need to get a ground back to the panel on these circuits. Which might mean fishing a wire down thru the first floor. There's a chimney chase I might do that in...
all the downstairs circuits are good--wired new and grounded back to the panel. In part why I hadn't caught this yet. Just assumed it was all that way.
I agree, the quick fix is GFI. Don't need to do anything with boxes, they're all fiberglass remodel boxes--sized appropriately.
Thx,
pat
"He did say the ground wires were just tucked away in the back of the box. All he has to do is take off the boot leg, attach the proper ground wire and insure that the grounds in the panel are attached to the ground bar."
Yeah, so I have to trace the circuit back and see where/if the grounds DO make it back.
Or, third, simply put in a 2 slot receptacle - local code may vary, of course, but it my understanding that this is a generally accepted practice.
If the device you're plugging in doesn't have a ground plug, the existence of a ground and ground wire is pretty much immaterial
"Ask not what the world needs. Ask what makes you come alive... then go do it. Because what the world needs is people who have come alive."
Howard Thurman
What you have is a code violation. You are correct with your two steps to solving the problem. I'm assuming that the 200A new service is installed to code. If that is the case, a grounding conductor from that circuit to the panel is acceptable to NEC '08 standards.
Another option would be to replace all affected plugs with GFCI receptacles. Be sure to use the "No equipment ground" sticker that comes with the new GFCI. This would be the quickest acceptable fix, give you fault protection, but you would not have the equipment grounding conductor for appliances.
Sensitive equipment like computers could even do better without the equipment ground. The best way is an isolated ground, but just putting a surge protector on your office equipment might be all you need.
"I'm assuming that the 200A new service is installed to code. If that is the case, a grounding conductor from that circuit to the panel is acceptable to NEC '08 standards. "
Yes--still has the inspector's tag on it. He still works in this area too!
That grounding conductor--can that just be a single strand of green 12ga copper--per circuit?
Thank you.
Someone please correct me if I'm wrong here....
If you plug something with a ground in that outlet like a fridge.... Touch the metal box and say a copper waterpipe? Aren't you now the neutral?
Oh Yes, affirmative.
But very difficult to get the fridge upstairs.
and then reach into the wall to grab the steel vent pipe.
I think that's why only these couple circuits running lights and plugs are wired this way--it's assumed to be the least risk.
The least risk would be to not make the ground energized by the neutral. I can think of a whole lotta other things you could plug in there besides a fridge.
It's rarely recommended to become part of a live circuit looking for a ground.
I'm not advocating for it.
Only speculating why it got wired that way in the first place.
Folks do this for two reasons: the convenience of three-prong receptacles, and to fool the home inspector.
We need to understand why this sort of thing is a bad idea - and for that, a little history helps.
Goal #1 is that we have a very low resistance path for faults to find their way back to the panel. This is what causes the fuse to blow, or the breaker to trip. That's what "grounding" is all about ... letting electricity that found itself in the wrong place (like the door handle of your fridge) race back to the panel, and trip the breaker, as fast as it can. The breaker removes the hazard when it trips.
Remember: electricity takes ALL paths back to that panel. If the ground and neutral are connected at any point after the panel, that ground will ALWAYS be carrying current. Open that ground, and you have an unprotected live 'wire,' so to speak. As someone suggested ... touch the fridge and the water faucet, and you've now made a complete path for current to flow.
The difference in that situation is ..... the system won't see a fault. Current will be limited by first flowing through the fridge's compressor, light, etc .... you're just "another neutral path." The breaker will never trip. The downside? It takes one heck of a lot less electricity to hurt / kill you, than it does to trip that breaker.
Now, for the history: At one time, it was common for manufacturers to connect the case of appliances to the neutral wire. The belief was that this provided some short circuit protection; a short in the appliance would blow the fuse immediately.
The only problem was that, if the 'hot' and 'neutral' got reversed somehow, the case was made 'live.' One result of this was the development of 'polarized' plugs, with the neutral blade too wide to enter the 'hot' slot on the receptacle.
It wasn't untill the 60's that the need to run a separate ground wire was recognized. Manufacturers stopped bonding the case to the neutral, connecting it to the ground wire instead.
In many way, the 60's was a real turning point; there were many innovations regarding shock protection. Having that third wire was the first. Double-insulated appliances, low voltage / limited current circuits, and, finally, GFCI's were also developed then.
Which, of course, brings us to the topic of this post: what to do when there's no third wire.
The best solution is to add that third wire, all the way back to the panel. Not an easy thing to do.
If all your appliances are double insulated - have two-prong plugs - you don't need that third wire at all.
But, let's assume you do need that third wire, and it isn't there. There's a fault, and you get a shock. That shock means that some of the current is going through you, rather than through the neutral wire. That's where the GFCI comes in.
A GFCI measures current 'going in' as well as current 'coming out.' If the two are not the same ... some current must be going somewhere else ... like through you. The GFCI will shut off the circuit when this happens.
The GFCI does NOT need a ground wire to operate properly. Alas, those plug-in testers do. Plug-in testers are a convenience; the test button on the GFCI is the real tester.
One of my first lessons in electric was at age 9 between the fridge and a gas stove. When the light was on, it was fun, when the compressor kicked on, not so much.
Renosteinke, you are referring to bonding. Large appliances were bonded in lieu of a grounding conductor. Now, bonding is required in the first means of disconnect, so no longer required at the appliance. Its hard to explain, and I don't quite understand all of it, but someone described it as a parrallel ground path--twice the potential for objectionable current. The neutral is a grounded conductor. Its sole purpose is to carry "extra" current back to its source. What exactly that "extra" current does when it gets there, I am not quite sure of. I just assumed it took the path to ground via the grounding electrode, but I think I'm wrong there. The grounding electrode is simply there for lightning strikes or a major fault from the line side of the service, you know, like a major fault off of the transformer.
Very clear explanation and history.
Thanks.
Kind of. You are the quickest path to ground, which used to be the neutral.
Insulated? Yes, it MUST be an insulated ground, whether it is in conduit or not. And it MUST go from the first plug in the circuit to the panel with no joints or splices. For one circuit, a #12 will be sufficient (as long as your not over about 80 feet from the panel). Just remember, it is always a safe bet and practice to use bigger size wire than required, but never smaller. It just decreases resistance with larger wire.
Thanks.
"That grounding conductor--can that just be a single strand of green 12ga copper--per circuit?"The ground wire conducts current only in the event of a ground fault. Its purpose is to trip the breaker so it doesn't have to be the same gauge as the conductors. Ground wire may be one wire size smaller than the circuit wires. That's why Romex 12-2 with ground has 14ga ground wire. BruceT
thanks,
pat
You are not correct.
True, at one time this was true. Currently made Romex, as well as other cable assemblies use a full size ground for #14, #12, and #10 circuits.
I repeat: You are no longer allowed to reduce the sige of the ground wire for small circuits.
The practice does continue with larger circuits, and the NEC provides table 250.122 for this purpose. It's not quite "one size."
Thanks for the correction. As a handyman, I don't do big jobs so I'm still working off the last few feet of a coil of cable that is 12/12/14. What's the rationale behind upgrading the ground? My 1965 house is wired with 12/12/16 and as easy as it is to break that small of a ground wire I can understand why they went up to 12/12/14 a few years later, but why upgrade to 12ga ground? BruceT