Will my GFI still work if the ground pin is missing?

No.

Power strips with legal plugs are available for around three bucks at Home Depot.

And as a licensed electrician, a fire marshal, a fire fighter, and a member of an ambulance corps, tell your son to replace his recepticals forthwith.

Thanks yet again for your invaluable knowledge and prompt responses, Arthur.

May I take the opportunity to wish you a very Merry Christmas since it's almost upon us?

Mike

quote:

tell your son to replace his recepticals forthwith.

I'm sure that this meant "first add green-wire safety grounding, and then replace the receptacles." Adding just U-ground receptacles without safety ground wiring gives a misleading and dangerous sense of security. (It also screws up installation of any TMCC/Legacy base wallwarts since you would expect the U-ground pin to connect to earth ground!)

I picked this up on a quick google search.

How a Ground Fault Circuit Interrupter (GFCI) Works



Figure 1: The 0.005 amp difference between the current going out and re- turning is sensed and the GFCI trips.

A GFCI (Ground Fault Circuit Interrupter) is a system that shuts down a protected electric circuit or opens it when it senses an unexpected loss of power, presumably to ground. GFCI protection devices constantly monitor and compare the amount of power flowing from the input hot wire and the amount of power returning on the output neutral wire. Any time the returning power drops even slightly below the amount being supplied (0.005A or more), the protection device will trip and therby open the circuit.

GFCI devices, including receptacles and circuit breakers, work by passing both the hot wire and the neutral wire through a sensor - such as a differential transformer (shown in the schematic above) - and connecting the sensor to a solenoid or relay that opens a switch built into the power conductors inside the device. See the schematic above for details.

You may have noticed that the working parts of a GFCI system don't include the circuit ground wire or the ground slot on a receptacle. That's because GFCIs are designed to protect us against a ground fault. A ground fault is defined as an unintended loss of power to ground through some path of least resistance - possibly through a person! The regular grounding system, on the other hand, protects the equipment that is attached to (or plugged into) the circuit against a ground fault in it. GFCI devices are designed to protect people, not equipment.

When it is working properly, a GFCI - or GFI - device will open and protect the circuit it is attached to - the fault path, which could be you! - 1 when the difference between the current coming into and the current going out of that fault path reaches 0.005 amperes. That's 5 milliamps, an amount most of us can't even sense. And thus a current we are safe passing through us. Making sure it is working properly is the reason for testing it once a month.

Note: sometimes "GFCI" is abbreviated "GFI".

So a ground fault device, either receptacle or circuit breaker, will work with out a ground wire present, though you have compromised equipment safety by lack of the gounding conductor. The Christmas tree lights don't have a ground wire, but a ground fault will still protect you and cause miserable problems on that outside circuit that is damp and wet.

quote:

Originally posted by Dale Manquen:

quote:

tell your son to replace his recepticals forthwith.

I'm sure that this meant "first add green-wire safety grounding, and then replace the receptacles." Adding just U-ground receptacles without safety ground wiring gives a misleading and dangerous sense of security. (It also screws up installation of any TMCC/Legacy base wallwarts since you would expect the U-ground pin to connect to earth ground!)

Grounds are an essential part of todays wiring systems, though there are provision for replacement of receptacles of like kind. The non-grounded receptacles, are not and should not be replaced with ground receptacles, as Dale mentioned, with out a ground wire present. There are still available though, usually by special order, two prong receptacles without the ground. To add grounds to some existing wiring systems can be a monumental task, usually involving complete rewire to houses build before 1970, which would includes wiring that has reduced ground sizes that can be suspect.

When he first takes a receptical out of the wall, he should check to see if there is:

Romex® wire with a ground lead, or BX armored cable, or metal conduit.

Any of these will be able to provide the requisite ground.

If none of the above is present, he needs to call a sparky.

I've found that many, but certainly not a majority, of older houses with two-prong outlets are also old enough to have been wired with BX. That's what I was thinking about when I gave my advice, and I hope he finds one of the above.

He can do a quick test with a voltmeter to see if there is a ground at the center screw of the outlet, before he even takes one out.

The majority of the wiring in my parents house, and in my first house was done with two wire non-metalic cable. No ground. Only the "wet" areas had two wire with ground.

when I purchased my 1948-built home, all receptacles were 2 prong style, but the house was wired with armor clad BX cable. I just added a ground wire secured to the box or BX clamp and replaced the outlet with grounded 3 prong style, properly wired.
the toughest part was determining which leads was hot or neutral, as the white coloring on the wire had mostly disappeared.

I snaked a #12 ground wire to all the kitchen, dining, basement and bath receptacles[new] in my parents two-wire romex house[1949 blt.] during 1966. Had to do a little plaster and dry wall patching in a few places.
Subsequent to the 1965 Code changes the State and Local departments recommended running a single ground wire as an approved upfit in older houses.

quote:

So will the GFI still work? I dont want to risk anyone getting electrocuted.

I just wanted to back up Mike CT's post above - your GFCI will still protect against ground faults even without a grounded socket.

quote:

Originally posted by Dewey Trogdon:
I snaked a #12 ground wire to all the kitchen, dining, basement and bath receptacles[new] in my parents two-wire romex house[1949 blt.] during 1966. Had to do a little plaster and dry wall patching in a few places.
Subsequent to the 1965 Code changes the State and Local departments recommended running a single ground wire as an approved upfit in older houses.

Yes I remember several older houses that had this type of upgrade. I often wondered at the effort it took to add the one wire v.s. change the complete cable assembly, which 1949 vintage may have been early thermoplastic insulations or not. It always amazed me how short the wire leads are in the boxes of these old house. The old copper wire had a tendency to age harden and become bittle, often breaking off as you tried to work with it.

I remember bidding/did not get the contract, a project for the local housing authority that was to add GFCI receptacles to about 100 bathroom units of a housing project, fairly recent in the last 15 to 20 years. There was no ground wire present, but at the time it was exceptable to add the GFI's with out grounds and the job was bid that way.

Sad note, watching 60 minutes last night, to see a lot of Cleveland vintage homes, "under water" as it's termed these days and striped of valuable commodities being torn down. Having spent a lot of time in homes like those, doing the needed repairs, I wonder how we got to this point.

The house in New Castle Pa looks a lot like what was being razed in Cleveland.
We are scheduled next week to do Christmas there as Mandy, my youngest, and her husband Zeke, soon to get a Master's degree from Carneige Mellon, will most likely be moving, not to see another Christmas in a wonderful older house that with some respect and hard work is a home.

quote:

Originally posted by Blystovski:

quote:

So will the GFI still work? I dont want to risk anyone getting electrocuted.

I just wanted to back up Mike CT's post above - your GFCI will still protect against ground faults even without a grounded socket.

Very true,

You can also use a ground fault breaker.I haven't seen a lot of BX in this area here in Virginia folks back then just didn't use it they just chose 2 wire romex.

I have been in several hundred houses that still have knob and tubing wiring put in around the turn of the last century .I know of one in particular that had it's gas lights converted to electricity .I also found some original wire mold which was just that . It was wood molding with 2 grooves cut in it .2 single wires were laid in the grooves and and a shaped wood cover was placed over them and held in place with finishing nails.Once it was painted it just looked like chair molding.

Another thing I've found often is houses built from about 1910 on up to 1940 often had the neutrals fused .They'd have a electrical panel but often in the attic or basement you'd find several fuse blocks one with a 15 amp fuse for the hot and a 30 amp fuse on the neutral or thats the way it was supposed to be.

Sometimes after years and years with no problems you'd get to that block and find out that somewhere along the line some joker put a 15 amp fuse in both.

I laugh because new kids today swear and pull their hair out trying to locate a problem in these old houses.They can spend a week looking and still not come up with anything.I'm lucky the Electricians I cut my teeth with started their careers in the 30's they were almost ready to retire when I came along.They taught me a lot.These were the same guys that wired the Mill Mountain Star and Victory Stadium(as seen in the 2000 movie "Remember the Titans")
They knew their stuff and were tuff as nails.

David

Safety meeting of the day. For those interested, you should be able to purchase a portable GFI protected multi-outlet that could easily be added to you Christmas display. Keep in mind the (PITA) involve with a GFI being used in a damp location.


Dave:
I remember those old knife switches and the double fuse, you forgot to mention that they were usually installed in a small framed opening lined with asbestos. Many residential services like this were only 110 volt and had two circuits one upstairs and one down. You could still find them around here in the late 80's.

Sparkies, why do GFCI's experience "early" failure? Over the years I have had several relatively young GFI's / GFCI's fail to hold a healthy circuit, had to replace.

What contributes to random GFCI short life cycles?

Additionally, what are the added qualities in a weather resistant GFCI? Would it be smart to use all "W" GFCI's in normal basements?

What is the very best (above the code) way to ground csst yellow sleeved gas line?

Just want to get as much mechanicals done b/4 the layout gets too far along.

csst (corrugated stainless steel tubing)is almost a default standard interior gas pipe in todays construction. Material is a tad higher than black iron however labor is pennies on the dollar.

This is an issue of failure, fires & explosions when lighting is involved. Code allows for a #6 on 3" or more of iron pipe within 5' of entrance for 200 amp or less service. Hpowever I am looking for above the code advice.

It seems as though there are savy electrictians on board. I am looking for reasonable redundancy.

quote:

Originally posted by Tom Tee:
Sparkies, why do GFCI's experience "early" failure? Over the years I have had several relatively young GFI's / GFCI's fail to hold a healthy circuit, had to replace. A lot like our model trains, untested until out of the box. There are better grades. Kitchen, laundry area GFI should be 20 amp rated.

What contributes to random GFCI short life cycles? They seem to be subject to surges. Lighting (other surges) seems to seek them out.

Additionally, what are the added qualities in a weather resistant GFCI? Would it be smart to use all "W" GFCI's in normal basements? Not a whole lot. Weather proof probably includes a gasketed cover. Common exterior practice is a bubble cover that allows for complete weather containment of a plugged in cord.

What is the very best (above the code) way to ground csst yellow sleeved gas line? Change the term to "Bond", which applies to both water and gas piping systems.

As we move both systems to more modern non metallic containment, especially from the street in to the residence, there are still components of both systems that are metal. A Bond to an electrical ground system, hopefully at Zero volts, is an assurance the metalic parts won't become energized. Commercially, structural steel is also required to be bonded to the electrical ground system. Most bonding to either water piping or gas piping is done with usually a #6 solid bare copper wire, I have seen #4 solid Aluminum wire used for the same purpose. As interior plumbing becomes more and more non-metallic, I'm sure there are code provisions for the small brass fittings, lav, shower, tub fixtures and water tanks, still metallic but I will admit to not being too keen on that, Most buildings I've worked in, had complete metallic water and gas systems. I'll push that one off to your local code enforcement officer who has the ultimate word anyway.



Just want to get as much mechanicals done b/4 the layout gets too far along.

The NEC (National Electrical code)does not allow ANY gas pipe to be used as an electrical ground. Water pipe, driven 10' x 5/8 rod & many times both but never never a gas pipe.

quote:

Originally posted by Ken M:
The NEC (National Electrical code)does not allow ANY gas pipe to be used as an electrical ground. Water pipe, driven 10' x 5/8 rod & many times both but never never a gas pipe.

We are not talking about a ground, note the distinction of the word "bond"

Instead of listening to opinions and advice from this forum I would suggest you consult a licensed electrical contractor and/or the AHJ (authority having jurisdiction, electrical inspector) in you area with any questions you may have regarding electrical installations.

While there is a electrical standard NEC (National Electrical Code) some areas may have requirements above that of the NEC. The NEC is a minimum requirement.

Any idiot can hook up a circuit and have it work. Remember the NEC is a fire code the circuit you hook up must be installed in a manner in which it will clear a fault safely, not just work.

This was not intended to offend anyone on this forum.

TMM

TMM, Your recomendation was my first path. Advice from three different contractors varied to the point they lost my confidence. One of them even wanted to clamp a bonding jumper on the csst hex nut, a specific violation according to the state inspector.

Sometimes I wonder if this csst is going to be the asbestos/lead paint/Chineese drywall of the future. The last thing I want to happen is to have people climbing over my layout years down the road changing out gas lines.

The advice I got from our state electrical inspection service was limited to only what was required. Safe, legal and insurable but minimum non the less.

Advice from two electrical forums was something like train forums....."How do I connect the transformer to the locomotive?......." Many original answers!

Before benchwork is too far along and track/wiring installed I believe it is wise to set up or service whatever basic tune-up the train room needs.

Just looking for additional input. Thanks.

Mike CT: Thanks for the reminder, how quick one forgets. I once was responsible for installing bonding jumpers on CH-46/CH-47 @ Boeing . tt

quote:

Originally posted by TMM:
Instead of listening to opinions and advice from this forum I would suggest you consult a licensed electrical contractor and/or the AHJ (authority having jurisdiction, electrical inspector) in you area with any questions you may have regarding electrical installations.

While there is a electrical standard NEC (National Electrical Code) some areas may have requirements above that of the NEC. The NEC is a minimum requirement.

Any idiot can hook up a circuit and have it work. Remember the NEC is a fire code the circuit you hook up must be installed in a manner in which it will clear a fault safely, not just work.

This was not intended to offend anyone on this forum.

TMM

No offense taken but the NEC is not a fire code .It sole purpose is to have a uniform set of rules and practices for the installation,repair and maintenance for electrical apparatus.
There's no doubt that this will also reduce the risk of fire to a minimum But the electrical code and fire code are not one in the same.

All 50 states are required to adopt the code with each revision and can enhance but not detract the requirements in the NEC. Most states just adopt the code into their uniform state code word for word as does the Uniform Code of Virginia
but no state can require less.

Theres been a lot of study's done concerning grounding.The company I worked for(American Electric Power) studies grounding extensively in their own Labs . They along with Dolby Labs pass this information along to the National Bureau of Standards who in turn compile and submit these findings and their recommendation to the NEC commitee for possible inclusion in the code book.

These studies have greatly improved our understanding for the need to have a good ground that's why the new requirements are for 2 ground rods driven 10 feet apart in un disturbed earth. Your also required to tie the rebar in house foundations to the ground system now and we have Arc protection in the bedrooms.
the secction on grounding is the largest section in the NEC.

Some locality's require more than whats in the code but most of it is not significant. I think that when it comes to the wiring in your house if you don't work in this constantly changing field all the time , the safest bet for you and your family is to hire someone like me to insure the job is done to your needed rquirements but above all is done safely .

David Cecil
Retired American Electric Power(26 years)
Virginia State Licensed Master Electrician
Virginia State Licensed Electrical contractor
Certified to work voltages up to 345,000 Volts

I just want to thank all of those who consistently take the time to share their valuable expertise on threads like this.

/QUOTE]

David Cecil
Retired American Electric Power(26 years)
Virginia State Licensed Master Electrician
Virginia State Licensed Electrical contractor
Certified to work voltages up to 345,000 Volts[/QUOTE]

David,

345,000 volts! I must say you have an "electric" personality.

AEP - great company!


Larry
Shade Tree Electrician from the Coal Mining Industry
EE - Member of IEEE
MSHA Certified for Low - Medium - High Voltage SUrface and Underground

Simple answer to the original question, not just no but H-E-Double hockey sticks NO!

I have a house built in 1965. Grounded only in the Kitchen, Baths, Laundry/Garage. As I have been working on the house over the years I have added grounds back to the panel where I could. I don't have a raised foundation or basement where this would be very simple. Ground anything you can at any opportunity you have.

I started reading this thread but stopped when I realized that I didn't understand it. So let me outline my problem and see if you guys can tell me why my GFI is tripping:

The electricity for my trains is on a circuit by itself; the breaker at the 200amp panel for that circuit is a 15 amp Cutler-Hammer GFI. I've had no problems with the 4 outlets on that circuit. I've used those outlets for my KW transformer, a shop vac, various power tools and a cordless phone charger. Not all at once, of course, but my point is I've used a variety of appliances on that circuit with no problems, OK? Enter a Dell pc (Optiplex GX260 SFF) and the circuit blows immediately on power up. With nothing else powered up, just this old pc (which still works well on other circuits in the house) the GFI blows when the pc power button is pushed. Why would a computer trigger the GFI?

The guy at Home Depot says I have an "open ground." The computer and monitor have grounded plugs; the powered pc speakers have a 2 prong plug.

Why am I having trouble with the pc?

In the picture below the pc is plugged into a different circuit in the attic.

common sense would pretty much answer this......no..

Agreed Aurthur, However the one problem I ran into was that when my home was built in 1965 ground was not required in rooms other than the Kitchen, Laundry, Garage and outside.

In my various remodel projects I have been adding ground wire back to the panel where I can.

 

I reviewed this thread, most of it from a year ago, Christmas 2011.  I did edit some of my input adding color to high-light questions and answers.  A lot of very good information, IMO.  Some very good technical safety discussion via this forum. 

But what do I know.

Thank you all who contributed.

Mike CT

" I would try the computer on another GFCI circuit,"

I'll try that and post the results, but it my be a while. The only other GFI circuits in my house are in the kitchen (You can imagine what a wreck it is the day after Christmas!) and the bathrooms (not much room in there either).

 

"If the computer has a metal cabinet and it is setting on a concrete floor it could be leaking through the chassis ground to the concrete."

Attic floor is made of plywood and the Dell pc cabinet is plastic, so ....

"most likely is leaking to the equipment ground conductor that is installed via the 3 prong plug and grounding system present."

Huh? Say that again in English, please. I don't understand it.

 

Some RFI filters shunt their energy to ground, which can trigger GFI circuits if conditions are right.  There can be RFI on the power supply, caused by line power conditions, and/or coupling of RF energy of the load. Computers can have a lot of RF energy on the load, especially if the decoupling circuits are not working effectively due to design flaws, component aging, etc.  So the root cause could be a number of

things, or a combination of non-optimal circumstances.

 

-Mark

quote:

Enter a Dell pc (Optiplex GX260 SFF) and the circuit blows immediately on power up. With nothing else powered up, just this old pc (which still works well on other circuits in the house) the GFI blows when the pc power button is pushed. Why would a computer trigger the GFI?

 

I had a somewhat similar experience with my vibratory polisher.

It would work fine on any non-GFI circuit, but after running a few minutes on a GFI circuit it would trip the GFI.

The issue turned out to be a faulty white wire running to the motor. It was making intermittent contact due to the wires breaking little by little from the vibration.  I reterminated the wire, and the problem was solved.

 

Arthur P has great advise...

 

I would offer also to be mindful of the existing wire in Guest's son's home...Replacing the existing two prong outlet with two prong u ground plugs will not meet code nor requirements for; the power strips circuit breaker function.  Most early homes had metal outlet boxes and a single continuos wire connecting all of these boxes back to the sub panel.  you need to add a ground jumper from the new outlet to the outlet box with a green ground clip to insure the CB trip functions.

 

juist my six bits...