GFCI circuit breakers

[Bob Niles]

Have a 50's house wired with 2 wire Romex with no ground and 2 prong outlets (so worn that plugs fall out). I would like to upgrade to 3 wire outlets and not rewire the house. I have a newer 100 amp sevice. I know I can replace outlets with CFCI outlet and use the 2 wire Romex but it is difficult to get the GFCI's into the small metal boxes (especially if the is more than 1 wire in the box. I have considered replacing the circuit breakers with GFCI breakers (I know they are expensive) and puting standard 3 wire outlets throughout the house. Anything wrong with my plan and does it meet most electrical codes?

[Steve]

I don't know how you can install a GFCI in a two wire circuit?? You need a ground for the GFCI to work at all.

However.. You don't need GFCI in interior outlets.. You are only required to have GFCI protection on outside and wet area outlet (bath, kitchen, basement,etc).. All other outlets should be three prong outlets, which means you still need 2 wire with ground electric cable.

Here is the deal for what you really should have.. You can install a GFCI breaker in the electrical panel and it will provide protection on any outlet on the breaker, howevery the circuit has to be 2 wire plus ground.

Or you can install a GFCI outlet as the first outlet in a string of outlets.. The GFCI, if wired properly, will provide circuit protection for the other outlet.

Anyway you to it, you need 2 wire with ground electric cable.. Sounds like it's time to pull in new cable.. This may not be as difficult as you think since modern plastic cable is smaller OD than the old Romex.. If the old stuff isn't stapled inside the walls, you can use the old cable to pull in the new stuff.. I just did this in my son's old 20s bungalow..

[red]

You do not need a ground wire for a GFCI to work. They will trip if there is any leakage current to ground regardless if the outlet is grounded. They will not protect against shorts though. Installing GFIs through out the house is genrally not a good idea. Most electronics are ALLOWED a certain amount of leakage current that will not do any damage to the device, but will trip a GFI, usually called phantom tripping. Very annoying.

Another option I did in my 1900 home is tied your ground to neutral. In the end all neutral and ground are the same thing.

If you feel unsafe, hire a professional

[Wade Lippman]

If you are trolling; please don't, some innocent will take you seriously. If you are serious, please hire a professional.

[Chris Lewis]

According to Steve :

GFCI's don't need grounds. Really and truly. They work by detecting current flow mismatch between hot and neutral. They do not need a ground to operate. See the NEC, CEC and the Electrical Wiring FAQ.

The simplest and most straight-forward (but not necessarily cheapest) way to install "shock protection" is to install GFCI breakers. NEC code _requires_ that 3 prong receptacles that are GFCI-protected but not grounded have "protected by GFCI" stickers on them.

If you have lots of problems installing GFCI outlets in old fashioned boxes, breakers are the way to go (unless you feel like swapping boxes.)

Further, you MUST NOT interconnect ground prongs on a circuit that don't have a real ground.

[Chris Lewis]

According to red :

Uh, no. No electronics is "permitted" to leak current to ground. If it does, you have a defective device. It is _possible_ in some cases that high current devices with lots of capacitance _may_ occasionally capacitively couple to ground (generally thought to be possible with medium to large motors), this is not true with electronics.

Uh, no again. This is _highly_ dangerous. The only interconnect between ground and neutral permitted is in the panel.

For example, if you ever lost a neutral connection back to the panel on a circuit, every grounded device on that circuit becomes a lethal hazard. Which _could_ include, for example, the furnace and all the ductwork. And possibly the plumbing. Etc.

[Wade Lippman]

My oven has no neutral (technically it has no ground, but has an "uninsulated neutral" which is attached to the oven sheetmetal, so it sounds like a ground to me). On bake, it sends 14a through both sides of the bottom element and 7a through one side of the top element. 7a comes back over the ground. This is how it was designed, and met code until 1996.

The body of the stove is grounded via the current carrying conductor, yet I have never gotten a shock off it. I figure that is partly because most everything I might touch is painted or plastic, but more importantly because I have so much more resistance than the real ground.

But, what would happen if I lost the ground connection? Then I would be the only path to ground. I would be in series with the heating element, but that wouldn't help me much. It sounds dangerous, but if it was allowed until 1996 it can't be that dangerous, can it?

Comments anyone...

[Chris Lewis]

According to Wade Lippman :

Consider:

It was permitted only until 1996.

It and dryers were the _only_ exception to the neutral/ground separation requirement in the NEC (in residential situations at least).

In Canada, three wire stoves and dryers haven't been permitted for at least 3 decades.

A stove or dryer circuit has only one device on it, beefier wiring and parts. Many of the loads are roughly balanced - meaning that the chassis isn't going to be far away from ground. Assign the probability of that killing you as, say, one in 10 million.

Now consider if you were doing that on _every_ circuit instead. Ordinary appliances - lots of them. Furnaces (with ductwork). Hot tubs. Swimming pools. Hifi and computer cabling. Your water heater (and hence all metallic plumbing). _Maybe_ even steel structural members and metallic studs. How do the probability worsen? A factor of a thousand or more? Probably.

Electrical systems are designed such that at least two faults are required before things become dangerous. Common-neutral/ground gets you only one fault away. In fact, coupling the ground and neutral together is MUCH more dangerous than having no ground at all.

[TimS]

Why? Can you not find new 2 'prong' outlets? Most non-computer equipment home equipment (small appliances, lights) still has 2 prong connectors. I think you would just be faking out yourself and the next guy. Decide some logical places for some 3 wire circuits (home office, entertainment center, work spaces) upgrade these to 3 conductors, upgrade wet areas to GFCI (also

3C), and replace the rest with new 2 prong outlets.

3 prong outlets, not grounded, are required to be marked as such, and I think the sticker would be as much a red flag as a 2 prong outlet would.

I don't think, for instance, most bedrooms in America contain any 3 conductor equipment anyway. If there were a 3 conductor outlet in the hall for tools (vacuum, buffer) that would certainly take care of needs.

[Tom Horne]

Your plan does meet the requirements for replacement of ungrounded receptacle outlets in the US NEC. The outlets would have to be labeled "No Equipment Ground" and "GFCI protected".

To answer your other question there is something wrong with your plan. The Equipment Grounding Conductor (EGC) does more than provide for human safety. By providing a low impedance path to ground it also provides for a degree of surge and spike protection to equipment that is connected to it. In the absence of an EGC surges and spikes may equalize through equipment to find ground in another utility such as the telephone, video, fuel gas, or plumbing lines. This process of equalizing through equipment is usually destructive.

There are two things you can do to compensate. One is to install a new line to serve any high value electronic equipment and avoid plugging such equipment in to the old ungrounded circuits. The other would be to install a whole house Transient Voltage Surge Suppresser (TVSS) at the service equipment to shunt such currents to ground before they can reach the equipment. For this to be effective your homes grounding electrode system should have a relatively low grounding impedance. I try to assure a system impedance of 10 ohms or less in my own work. It should be obvious that Grounding Electrode Systems consisting of only two driven eight foot rods will seldom achieve this low an impedance. It may be necessary to drive coupled rods to a depth of thirty or more feet by using a hammer drill, or to excavate a trench into which you will bury a ground ring or multiple horizontal rods. The grounding electrodes have to be driven or buried deep enough to be in permanently moist soil. If permanently moist soil can not be practically reached then several electrodes or a large area electrode; such as a true UFER; will have to be constructed.

-- Tom Horne

[Childfree Scott]

If it's 2 wire Romex then you are out of luck. Just replace them with new two prong outlets. Now I've seen it done with two wire with armored cable and the person put in three plug receptacles and used the armor as a ground (wire between the ground lead on receptacle and grounded metal junction box.

As for the GFCI's yes the old junction boxes are too small to put them in. Just use GFCI breakers.

[Steve Smith]

As other's have said: Don't tie the ground to the neutral, this is only done at the service entrance.

If you can't fit GFCI receptacles in the existing boxes you can always install a GFCI recpt. for each circuit right beside the panel in a new, bigger outlet box. On the back of GFCIs there are two sets of terminals, one for line (from fuse/breaker) and the other for load which can then go on to protect other outlets. This method will be cheaper than buying GFCI breakers, which are notoriously expensive.

Replace the worn two-prong outlets with new two prong outlets. If you use three prong outlets you need to attach ugly stickers to them.

-- Steve

[TURTLE]

This is Turtle.

Don't try to explain to a Troll what is right and wrong. he is right all the time in his head.

TURTLE