2-prong outlets: Narrative examples?

[Kenton H. Shepard, CMI]

I'd like to see examples of narratives describing home electrical systems with ungrounded 2-prong outlets if anyone would like to share them. -Kent

[Jeffrey R. Pope]

Courtesy of InspectVue (Keith Swift). . .

The ungrounded and obsolete outlets should be upgraded to include more modern and safer ones, which provide a pathway for the current to travel harmlessly to ground.

[ccbrands1]

I'm assuming here that the 2 prong outlets are on a 2 wire electrical system.

I understand the safety issue involved.

Going by the quote, I should be recommending that all 2 wire outlets be replaced with grounded ones?

How is that expressed to the buyer?

Most of the time on a two wire system, wouldn't that require totally rewiring the outlet?

I would also like a narrative of how to explain a 2 wire system to clients.

[Paul W. Abernathy]

"Ungrounded 2-prong electrical outlets do not provide an effective pathway for equipment grounding procedures. The recommendation is to consult a licensed electrical contractor for your options."

[Paul W. Abernathy]

CC.....as I stated the electrical contractor will give them these options:

(3) Non–grounding-Type Receptacles.

Where grounding
means does not exist in the receptacle enclosure, the installation
shall comply with (D)(3)(a), (D)(3)(b), or (D)(3)(c).

(a) A non–grounding-type receptacle(s) shall be permitted
to be replaced with another non–grounding-type receptacle(s).

(b) A non–grounding-type receptacle(s) shall be permitted
to be replaced with a ground-fault circuit interrupter type
of receptacle(s). These receptacles shall be marked
"No Equipment Ground." An equipment grounding conductor
shall not be connected from the ground-fault circuitinterrupter-
type receptacle to any outlet supplied from the
ground-fault circuit-interrupter receptacle.

(c) A non–grounding-type receptacle(s) shall be permitted
to be replaced with a grounding-type receptacle(s)
where supplied through a ground-fault circuit interrupter.
Grounding-type receptacles supplied through the groundfault
circuit interrupter shall be marked "GFCI Protected"
and "No Equipment Ground." An equipment grounding
conductor shall not be connected between the groundingtype
receptacles.

Hope this explains the options they have....

[Paul W. Abernathy]

Also....figured I would throw in....Yes, the circuit can also be protected by a GFCI Breaker as well....labeling still applies.......

[Jeffrey R. Pope]

Paul,

Is GFCI protection required when three-prong (grounding-type) receptacles are palced on two-wire (ungrounded) branch circuits?

[ccbrands1]

I think I get it, Paul.

Let me know if I'm off here.

So per (D)(3)(C)

If you had five 2 prong receptacles on 1 circuit, you could replace the first receptacle in the circuit with a GFCI (labeled no ground) then replace the 4 downstream receptacles with standard 3 prong receptacles (labeled no ground & GFCI protected)

Makes sense in my head. Am I understanding correctly? Would this be legal?

If this is the case, Jeff, then not all 2 prong receptacle would need to be replaced with GFCI, just the first receptacle in the circuit.

RIGHT???!!!

[Paul W. Abernathy]

CC,

You are correct. If you choose to replace the 2 prong with 3 prong receptacles...you can ONLY do it as listed in my example of # 2 and # 3....option # 1 is simply to replace existing 2 Prong with 2 prong replacements only...

Jeff, that is correct....IF someone wishes to use 3 prong on an existing 2-wire circuit.....replacing with 3 prong itself is WRONG unless they use the options shown in my previous statement which at that point the NEC makes the allowance for.

Hope that answers it...

[Joe Funderburk, CMI]

Many receptacles were 2-prong ungrounded receptacles. While acceptable, this older wiring method limits the use of some modern appliances such as refrigerators, washing machines, computers, etc., that require a grounding conductor. Dedicated circuits may have to be run to properly use such appliances.

[Jae Williams]

http://www.cpsc.gov/cpscpub/pubs/524.html

[Jae Williams]

...and for three-prong outlets on a two-wire system...

The use of three-slot grounded type outlets gives the impression that safety protection is present in the circuit, when in reality it is not. Older style two-slot outlets are still available and should be installed to eliminate this false sense of security. Three-slot outlets are more convenient and are often installed without consideration to this situation.

[Doug Edwards, CMI]

Another determining factor is the cost of the two prong versus the cost of the 3 prong. Checking for myself I found the replacement 2 prongs were about 5 times more expensive than buying a standard 3 prong "grounded" outlet. Many folks will just buy the new cheaper 3 prong to "solve the problem" and figure it is okay.

[Paul W. Abernathy]

This is why these two options are the best.....and option (b) being the less expensive of the two....BUT does require some HOMEWORK to ensure the FIRST receptacle in the chain is found.

let us also remember that a GFCI receptacle has listed in it's manual how many receptacles it can protect downstream...the number is not INFINITY...lol

(b) A non–grounding-type receptacle(s) shall be permitted
to be replaced with a ground-fault circuit interrupter type
of receptacle(s). These receptacles shall be marked
"No Equipment Ground." An equipment grounding conductor
shall not be connected from the ground-fault circuitinterrupter-
type receptacle to any outlet supplied from the
ground-fault circuit-interrupter receptacle.

(c) A non–grounding-type receptacle(s) shall be permitted
to be replaced with a grounding-type receptacle(s)
where supplied through a ground-fault circuit interrupter.
Grounding-type receptacles supplied through the groundfault
circuit interrupter shall be marked "GFCI Protected"
and "No Equipment Ground." An equipment grounding
conductor shall not be connected between the groundingtype
receptacles.

Here is something from the 1999 NEC...but still rings true for the 2002 NEC...just the article numbers have changed a bit...but a nice illustration to go with the things I listed earlier....

[brian winkle]

Originally Posted by jfunderburk

Many receptacles were 2-prong ungrounded receptacles. While acceptable, this older wiring method limits the use of some modern appliances such as refrigerators, washing machines, computers, etc., that require a grounding conductor. Dedicated circuits may have to be run to properly use such appliances.

Joe, this is the most sensible statement I have seen regarding 2 wire receptacles. After all, most household lamps and appliances are 2 wire. I do not believe it is wise to inform a buyer/seller that a two wire system should be completely replaced which can certainly cause panic on their part. It can be updated as needed like you advise in your statement.

Be aware that while GFCI protection is a legal way to install a 3 wire recep on a two wire system, it is still a code violation to plug an appliance into that GFCI if the manufacturer states that the appliance requires a grounded circuit.