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Peg Keefe · Jul 20, 2013, 08:02 PM

Older house with 2-prong outlets in plastic wiring. Can you ground these outlets by replacing them with GFI to ground them or do you need to run a ground wire to each outlet?

donf · Jul 21, 2013, 12:59 PM

In order to properly ground each receptacle you would have to pull new cable from the main service panelboard to the receptacles and new cables from each receptacles to the next receptacle in the chain. You cannot just pull a ground wire to each receptacle.

The alternative is to use GFCI receptacles because they do not require the use of a ground to function and provide you the three prong receptacle you need.

ma0641 · Jul 21, 2013, 03:53 PM

GFIs don't ground anything, they trip when unbalanced current is noted. Use the GFI and put the sticker on that says "No equipment ground ".

donf · Jul 21, 2013, 05:13 PM

Isn't that what I said in my response?

ma0641 · Jul 21, 2013, 06:24 PM

Originally Posted by donf

Isn't that what I said in my response?

Just another comment. Do need to be marked.

donf · Jul 22, 2013, 10:54 AM

Actually I like your response better than mine. I just was a tiny bit peevish! :)

smoothy · Jul 22, 2013, 11:25 AM

You can't assume non-technical people understand the function of a ground.. or that future owners or residents of a house would think incorrectly that it has a three prong outlet... so it MUST be grounded... and not know the risks involved.

donf · Jul 22, 2013, 01:22 PM

Hold it,

Use of a GFCI receptacle is acceptable under the NEC. However, the receptacle must be marked that it is an un-grounded receptacle. MA is correct.

stanfortyman · Jul 22, 2013, 02:47 PM

You can't assume non-technical people understand the function of a ground.. or that future owners or residents of a house would think incorrectly that it has a three prong outlet... so it MUST be grounded... and not know the risks involved.

Smoothy, this is not true.
As said, a non-grounding circuit can have three prong receptacles if GFI protected. You are supposed to put the "No equipment ground" stickers on all un-grounded 3-prong receptacles, but I have never seen them included with the Cooper GFIs I buy.

smoothy · Jul 22, 2013, 04:05 PM

I think I wasn't as clear as I thought with what I was trying to say... in that... even if stickers are put on... they get scraped off by kids, fall off... if outlets are changed they are forgotten... etc.

I don't think the average homeowner is going to spend much time looking for stickers either (with fuel at around $4.00 a gallon.
.
And consider replacing outlets is a job a lot of homeowners do themselves...

And at some point in time in the future you have someone living in a house with three prong outlets... and ungrounded wiring... assuming they have actual working grounds.

I'm in agreement with you guys... but from the perspective of someone reading this that barely knows how to use a screwdriver... a lot of this would wiz right over their heads.

stanfortyman · Jul 22, 2013, 04:36 PM

And at some point in time in the future you have someone living in a house with three prong outlets... and ungrounded wiring... assuming they have actual working grounds.

And other than maybe a computer UPS or power strip that will squawk about it, why is this an issue?

smoothy · Jul 22, 2013, 05:48 PM

Originally Posted by stanfortyman

And other than maybe a computer UPS or power strip that will squawk about it, why is this an issue?

Yard sale power tools... if a cable line became energized.. do we know for certain the house isn't on a slab...

stanfortyman · Jul 23, 2013, 04:11 AM

Yard sale power tools... if a cable line became energized.. do we know for certain the house isn't on a slab...

And in each case the GFI make it safe.
Are you somehow suggesting this code complaint practice is not safe?

smoothy · Jul 23, 2013, 04:36 AM

Originally Posted by stanfortyman

And in each case the GFI make it safe.
Are you somehow suggesting this code complaint practice is not safe?

The sticker thing is... for a number of reasons. They fall off, get pealed off by small kids... or by adults that don't like seeing them, future replacement. Leaving new parts unlabled.

You could expect Electricians to do it... but this is work many more handymen and homeowners and renters do themselves.

This isn't NEC code but its what OSHA has to say on the topic and why.

https://www.osha.gov/dte/grant_mater...pant_guide.pdf

hkstroud · Jul 23, 2013, 07:37 AM

Page 10 of your reference.

The ground fault circuit interrupter (GFCI) works by using the above principles. It measures total
Current on the hot side and total current on the neutral side of the circuit. They are supposed to be
Equal. If these two currents differ from each other by
More than 5 milliamps
(plus or minus 1 mA),
The GFCI acts as a fast-acting circuit breaker and shuts off the electricity within 1/40 of 1 second.
You can still feel this small amount of current, but it will quickly shut off.

stanfortyman · Jul 23, 2013, 01:32 PM

The sticker thing is... for a number of reasons. They fall off, get pealed off by small kids... or by adults that don't like seeing them, future replacement. Leaving new parts unlabled.

You could expect Electricians to do it... but this is work many more handymen and homeowners and renters do themselves.

So you are saying not having the stickers on is not safe?
How so?

smoothy · Jul 23, 2013, 02:46 PM

Originally Posted by stanfortyman

So you are saying not having the stickers on is not safe?
How so?

You will have a homeowner that THINKS they have a grounded outlet and doesn't.

If they also manage to get the white and black reversed ( I found outlets like that in my house) and they have a fault in a piece of equipment... then yeah.. it can be dangerous in the right circumstances. Not in all circumstances.

What is second nature to you guys... I might have to think about a moment (not talking about NEC Code stuff), being an Electronic Engineer.. not an electrical engineer or Master electrician... and your average homeowner wouldn't even know enough about to ask someone.

stanfortyman · Jul 23, 2013, 04:43 PM

You will have a homeowner that THINKS they have a grounded outlet and doesn't.

Once again, so? It's GFI protected, isn't it?

If they also manage to get the white and black reversed ( I found outlets like that in my house)

Now just how is this supposed to happen if the receptacles are already installed?

smoothy · Jul 23, 2013, 05:15 PM

Originally Posted by stanfortyman

Once again, so? It's GFI protected, isn't it?

Now just how is this supposed to happen if the receptacles are already installed?

The OP's question was.

Older house with 2-prong outlets in plastic wiring. Can you ground these outlets by replacing them with GFI to ground them or do you need to run a ground wire to each outlet?

You don't ground something without a ground present to ground them to..

As to the last part... its an old house... what are the odds those are the original outlets?

I found several in my house wired backwards (its anyone's guess when that actually happened) which was new enough to have grounded cabling... and outlets... with a upgraded service and 200amp service done less than 20 years ago.. the house is 50 years old. My parents house that is 5 years older doesn't.

First thing you learn in school is never make assumptions... particularly when working with hazardous voltages. You check and verify.

Incidentally... I get the impression you might think I'm second guessing you... but I'm not.

stanfortyman · Jul 23, 2013, 05:33 PM

The whole point is: It is a legal and safe practice to replace a two-prong receptacle with a GFI receptacle (or GFI breaker the circuit), wired using the load terminals for downstream, then replacing the other two-prongers on that circuit with three-prongers.
I was not talking about protecting old two-prongers, or leaving old receptacles. That's why I thought it strange about worrying about reversed polarity receptacles and all. That's not what I was talking about.

Bottom line is, it is legal and safe. Safer than leaving the old two-prongers that are not GFI protected.
No one (except the OP) suggested that a GFI will provide a ground. This was cleared up early in the thread.