The best method is to run new circuit conductors.
A ground can be run back to the panel, but is often as much work as just running a new piece of NM.
A ground wire NOT in the cable bundle will also NOT be as effective at shunting surges away.

All settled. Gonna disconnect the outlet (that I wanna change) from where it is receiving its power. Will run new wire with ground directly to the circuit panel. I had it all explained to me at a different M*****'s. This guy was VERY helpful---and, MADE sure I understood everything. Wish there were more guys like him at some of these stores!

For the record, big box stores are probably the worst place to ask for advice of any kind. Granted, you do sometimes run across some people who do know what they are talking about, but the majority know very little about everything. The problem is they pass it off as if they actually do know what they are talking about.

I have another important concern: You say almost every other outlet in your house is a three prong. Are you sure that they are indeed properly grounded? I find it strange that some circuits would be grounded and others wouldn't. Just because there is a three prong receptacle doesn't mean its actually grounded. Many homeowners just slap a three prong receptacle on an ungrounded circuit and call it a day. If you haven't already, please check to see that all circuits with three prong receptacles are properly grounded.

our house has mostly 3 prong, properly grounded outlets, with 2 rooms having older wiring with 2 prong un grounded outlets because we have remodeled most of the house and re wired.

i think that the op needs to state weather or not there had been any remodeling or additions to the house that would nessicitate the upgrading of electrical.

Some folks actually upgrade wiring for the extra safety.
Keep in mind the code is the MINIMUM.
If you want to use a electronics and have any type of surge protection operate correctly you need the ground anyway.

Any hazards with wiring a 3 prong plug to an ungrounded circuit??

Thanks,
Al

wow you're asking this when you have read this post? Yes! read the post.

Wow! I did read the post, and like most posts there are several different people saying several different things, which is why I asked the question directly. Maybe I'm missing it, but I don't think it states anywhere here that it is hazardous--just needed if you want a surge protector to work properly.

I've lived in my home, which has 3 prong plugs, for a few months. I had no reason to assume they weren't grounded until I purchased a surge protector and the "grounded" LED didn't light. I am now concerned that the previous home owner "just slap a three prong receptacle on an ungrounded circuit and call it a day" as rtscoach stated.

Spencer, I'm not an electrician, and have never claimed to be. I'm just a homeowner who is trying to figure out if I should be concerned. I hope you have more patience outside of this forum.

Al

its a hazard and a code violation to hook a 3 prong plug to an ungrounded circuit.

"its a hazard and a code violation to hook a 3 prong plug to an ungrounded circuit."

Unless that circuit is protected by an GFCI and properly labeled (no equipment ground, GFCI protected).

"Unless that circuit is protected by an GFCI and properly labeled (no equipment ground, GFCI protected)".

Yes true but now you have a 3 prong receptacle where you can hardly plug anything into it, as it is also a violation to plug anything into it when the manufacturer states "must be plugged into a grounded receptacle" which just about all do.

Still though, I think it is a reasonable solution to those who truly can't afford to re wire.

Thanks guys,

I'm officially concerned and still a bit confused so please bear with me.

I took my surge protector around the house, and even though all the rooms have 3 prong plugs,the only rooms that light the "ground" led on my surge protector are the kitchen and the bathroom. The bathroom has GFCI outlets, and the kithcen was remodeled just before I purchased the house so I guess those outlets were updated then.

Could you please tell me what my options are for the rest of the outlets. At this point, I don't think I could afford to pay an electrician to rewire the other rooms.

Thanks again,
Al

Al: As stated earlier in this post, you can protect the 3-prong receptacles with a GFCI, run a ground wire to each, or replace them with a 2-prong receptacle.

And don't be so sure the bathroom and kitchen receptacles are properly grounded. Some unknowing handyperson may have installed a jumper between the neutral and ground so that the receptacle appears to be grounded when a plugin tester is used, but it is not, and may create an even greater hazard than the ungrounded 3-prong receptacle

Thanks normel,

I removed the cover and pulled out the receptacle on one of the outlets in the kitchen, and there's a bare wire wrapped around the cables where they are secured to the box when they enter/exit--safe to say they're grounded??

I did the same in the bathroom, and the bare wire is atteached to the green screw.

In order to keep cost down, I'm think about replacing all the other receptacles with 2 prong (something that I should be able to do), and hiring an electrician to rewire the receptacles where I would want to use a surge protector or air conditioning, which are the only things I can think of that have a 3 prong plug.

To keep cost down even more, I'm thinking about buying a homewiring book (something I'll probably need as a new homeowner)and maybe do the rewire myself. Is that something anyone would advise against??

Thanks again,
Al

I am a renter. And this is what I found done at this old 1930's house we are in now.
They took a #12 bare copper wire scewed it to the 3 prong outlet box,went thru the wall outside to a 4ft. grounding rod in the ground. When I asked the county code enforcement officer,he stated that that was okay and safe ..
So much for N.Calif. hahaha STRANGE !!

There are circumstance where that independent ground rod could be quite dangerous. A hot to ground short in an appliance or tool would have its fault current limited by the resistance of the soil between that rod and the grounding electrode system attached to the service panel. Depending on soil conditions that could be less than 5 ohms to more than 25 ohms. Maybe a lot more with only 4 ft rod. So anywhere from less than 5 amps to more than 25 would flow. It would likely take quite a while for the breaker to trip if it ever did.

Arcing at the fault point could start a fire before tripped off. If it were a tool, most of the 120 volts would appear between the metal case you are holding and any other "ground" point that you might be touching.

While we are on this subject, I have a question. While converting a bedroom to a home office, it was important to have a grounded outlet for the surge protection. I ran a bare 12 gauge wire from the outlet ground to a cold water copper pipe (we were remodeling the bath through the wall and it was very handy). We have old plumbing that is all copper and the newer entrance panel required that the ground from the breaker box be directly grounded to the water pipe entrance into the house. That means that the pipes are connected to the ground at the main breaker box. It all seems to be very adequate grounding to me, but I am curious if anyone sees any problem with it.

Dale P

I think the most important thing to understand is that the third wire or ground wire is an equipment ground and is typically connected to the shell of whatever is plugged into the outlet. It is there for your safety, it does not normally conduct current and is not subject to any surges unless a fault is in process. The most important thing is that it be connected to the earth. Code wants all the grounds to terminate at a single point. That point can be one or several ground rods 8' or longer connected together with a heavy bare copper wire (The resistance must be less then 25 ohms to earth). I use #4 as a minimum. A separate #12 or #14 Copper wire (green insulation is the best) to the outlets is ok and may be the only practical solution at the present time. These need to be taken back to the ground rods (the ground rods may be also connected to a water pipe. This is a separate connection and only connects with the power neutral at one point. The ground rod wire probably would be ok. You should ask your inspector to be sure. These safety grounds are very important where you can come in contact with the electrical system and the earth ground such as near any device connected to the water such as washer, dryer, sink, etc. Kitchens, garages, outside and bathrooms are critical.

Gil, ground rods are NOT the safety ground you are referrring to, This is a very common misconception.
The ground rods and electrodes have NOTHING to do with breakers tripping or "grounding" anything.
The earth does NOT "provide" a ground.

This is accomplished by the neutral to ground bond in the main panel. All the grounds and neutrals are connected in this panel and that is where your safety "ground" comes from.

A short circuit or overload is wanting to trip a breaker. This current flows on the neutral wire back to the panel and subsequently back to the transformer. The breakers in the panel stop the ground fault current from reaching the transformer. The breaker also protect the circuit conductors from overload or neutral faults.

A house would perform perfectly fine without any grounding electrodes. Breakers would trip normally.
Grounding electrodes serve a completely different purpose.

I stand by my statement.

You might read the current information etc. You are correct they are bonded together at only one place in an instillation; some locations now require that they are not. You are also required to have separate bars for the neutral and safety ground, if they are the same why? Why do they only want a single point ground?

The earth is the ground and the reference point and hence the term ground. Why do you think the 25 ohm or less ground rod resistance to earth requirement exists? I know of farmers that ran a single wire to an outbuilding and drove a ground rod for the other to save money and the lights worked just fine.

Your assumption of a ground fault does not compute. You describe a phase to neutral fault not a ground fault.

Remove the bonding screw and connect a breaker to the safety ground then you have a ground fault and if the system is correct the breaker will trip. To make it easy just connect a test light between them, if it does not light you have a problem.

Whenever a current flows through a conductor there is a voltage drop, ohms law defines this. You do not want that drop in the ground circuit. The difference can do interesting things if you get between them. Do you want to sit on the ground and when you turn on the power tool gives you a zap? The neutral carries only the difference current between the phases, the ground caries none.

I assume you have four wires in your box, two phases (black and/or red), one neutral (white or bare) and one ground (green or bare separate from the neutral). All branch panels are connected with four wires, 220 assumed, one neutral, two phases and one ground. The normal transformer that feeds a house has a center taped winding with the center tap connected to the ground and called the neutral.

If the neutral fails the safety ground will carry the current and protect your system that is why they upped the wire size requirement for the ground many years ago. Then you could get 12X2 with a smaller gauge ground #16 I think). The Edison transformer is also grounded via a ground rod on both the primary and secondary sides.

I know this first hand, I have a neighbor with an open neutral and his ground current is coming in my city water pipe as well as the neighbors. I see 10 Â 30 amps on the water and gas pipes, even with my Edison power disconnected. Edison says this is normal and cannot do anything about it. They also told me it is very common in older subs and was caused by open neutrals..

The equation is resolved with the addition of a CFGI breaker, if the neutral opens it will trip if there is any connection to the earth. AFCIs take care of the arcing fault problems. CH makes a combo that costs about the same as the AFCI.

I have a transfer panel out side and that is where they are bonded together as code requires. Four conductors connect each panel and sub panel. There is no bonding screw in any of the panels inside. The inspector did check this.

You are correct in the normal flow of current. GFCI breakers measure the current in both wires, if they are more then about five mA different it trips. Where do you suppose the current is flowing?

gilshultz wrote:
>the third wire or ground wire is an equipment ground and is typically connected to
>the shell of whatever is plugged into the outlet. It is there for your safety, it does not
>normally conduct current and is not subject to any surges unless a fault is in process.

All true.

>The most important thing is that it be connected to the earth.

NOT TRUE. For a hot-to-chassis fault, the important thing is that the grounding (green) wire be connected to neutral back at the first panel. That is where the current needs to go, so that it can have a low resistance path back tot he transformer center tap. The connection to earth is irrelevant for this situation.

The reason code wants only a single-point connection between neutral and ground in your house is that multiple points cause the neutral currents to flow on portions of the groundign system. Open connections could cause voltages to appear between things that were intended to be at ground potential. Notice that the idea is to keep or get the currents on the neutral to the greatest extent possible.

Notice that 125 volts and 25 ohms of ground resistance means a dead short to ground, in the absence of any metallic path, could be limited to only 5 amps which would not trip breakers. (Some soil conditions would have lower resistance and more current.) That is why the earth connection is not relied on for most safety purposes and lighting a building with only one wire is a very bad idea.

The main purposes of the earth connection are to provide a lightning path and a path for the rare but potentially disastrous event of the 14 kV in the transformer shorting to the 120/240 wires.

The bonding of pipes is not so much to provide an earth ground as to prevent voltages between the pipes and the chassis of appliances should something go wrong. It also as a side effect tends to lower the resistance of the connection to the world.

As a side effect of bonding of pipes, an open-neutral can cause currents to flow in various metallic paths that connect houses. This may or may not be in the power company wiring and if they have checked their part, then your neighbors need to have an electrician examine their meter-to-panel connection.

Gil, if I read correctly, you say your water pipes have fault current flowing through them because of a bad neutral? This would only be possible if the SERVICE neutral was where there was a connection problem. Current of any kind will always take the path of least resistance. In the case of a fault, yes the bare ground WILL carry the current, but only to the place where it is bonded to the service neutral, then will flow from there to the center tap of the transformer.

If the case with your neighbor is a bad service neutral, well he needs to get someone to help him ASAP.