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#119778 - 01/22/05 06:07 PM Use with Caution
Webmaster Offline


Registered: 10/07/00
Posts: 3142
Loc: NY, USA
These are a bane of my existence. I wonder how many people (I don't happen to be one) have actually seen these devices used according to their listing and labeling instructions. What does everyone think about the potential hazard with these devices... after all, they are UL approved.

Glenn (safetygem)

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#119779 - 01/22/05 06:13 PM Re: Use with Caution
CTwireman Offline

Registered: 02/07/02
Posts: 839
Loc: Connecticut, USA
Very simple: They are used incorrectly 99.9% of the time.

#119780 - 01/23/05 05:07 AM Re: Use with Caution
CharlieE Offline

Registered: 04/23/04
Posts: 204
Loc: Indianapolis
UL lists them to be used in accordance with the manufacturers directions. The problem, as I see it, is that Joe Homeowner doesn't read the directions, doesn't care as long as it works, and will not complain until someone is hurt. Now it is someone else's fault (UL?) and let the attorneys get them some money for their stupidity.

- - - - - - - - - - - - - - - - - - - - - - - - - - -
Charlie Eldridge, Indianapolis, Utility Power Guy
Charlie Eldridge, Indianapolis Utility Power Guy

#119781 - 01/23/05 03:00 PM Re: Use with Caution
renosteinke Offline
Cat Servant

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
I will admit to frequently having to use these things....when I use my OSHA mandated 3-wire extension cord to power my two-wire, double insulated tools from an older ungrounded system.

#119782 - 01/23/05 03:48 PM Re: Use with Caution
electure Offline


Registered: 12/24/00
Posts: 4226
Loc: Fullerton, CA USA
Do you think that a homeowner who knows how to use one of these gizmos correctly would be smart enough to know how to change the receptacle?
Seems to me that after they test the cover plate screw and find it grounded, that would be the logical step.
These are almost "produced to be misused" IMO.

#119783 - 01/23/05 04:56 PM Re: Use with Caution
n1ist Offline

Registered: 02/13/02
Posts: 176
Loc: Malden MA
I have used these back when I was renting an apartment (and therefore could not change the receptacles myself) for a window AC. I did test that the box was grounded. In my house, I would of course change the recept to a 3-wire or at least a labeled GFCI.


#119784 - 01/24/05 12:16 PM Re: Use with Caution
Bjarney Offline

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Realize that for decades there used to be a far more treacherous version of grounding adapter—it had a ‘flying’ ground lead, that could contact the ungroudned or ”hot” blade of the adapter and unintentionally energize an appliance enclosure.

It is fortunate that GFCIs are permitted to be installed on 2-wire (ungrounded) breach circuits.

Maybe Canadian members can verify that the pictured adapter was NEVER permitted by CSA?

#119785 - 01/24/05 01:21 PM Re: Use with Caution
SolarPowered Offline

Registered: 07/05/04
Posts: 615
Loc: Palo Alto, CA, USA
These things are "legal" because of the fiction that they're supposed to be grounded through the cover-plate screw on a grounded box. The reality is that everybody, from the manufacturer, to UL, to the store, to the user, knows full well that the real purpose is to allow 3-pronged devices to connect to older, ungrounded receptacles. The alternative is that people would be cutting off a lot more ground pins than they already are, making a bad situation even worse. (That is, if they leave the ground pin intact, then there is at least the possibility that the appliance will be properly grounded on occasions when there is a grounded receptacle available.)

So, we have the legal fiction that these things are going to be connected to grounded screws. Why we need to do things this way, I don't know. (The answer probably starts out with, "What do you call a thousand lawyers chained together on the bottom of the ocean?" But that's another thread...) But, there's no reason to get too anal about these gadgets--they're intended to be used the way they're being used.

[This message has been edited by SolarPowered (edited 01-24-2005).]

#172255 - 12/16/07 08:00 PM Re: Use with Caution [Re: Bjarney]
Theelectrikid Offline

Registered: 04/30/04
Posts: 854
Loc: Levittown, PA

Was going to post a new thread, but did some searching and found this old one...

 Originally Posted By: Bjarney

Realize that for decades there used to be a far more treacherous version of grounding adapter—it had a ‘flying’ ground lead, that could contact the ungroudned or ”hot” blade of the adapter and unintentionally energize an appliance enclosure.

The local Ace now carries these brand new. The owner of the store ordered the "legal" ones, and got these instead. \:\(

Ian A.
Is there anyone on board who knows how to fly a plane?

#172258 - 12/16/07 08:59 PM Re: Use with Caution [Re: Theelectrikid]
sparkyinak Offline

Registered: 07/08/07
Posts: 1288
Loc: Alaska
Many three prong to two prong adapters are actually listed. The problem is the only maintain their listing if installed IAW installation instructions. The proble is the instuctions states that the fork must be attached to a grounded screw. It you still have a two wire system like I do, technically you can not use them since the center screw is not grounded. NEC allows the run of a ground wire but the hassle it takes to run wire in old work, with a few dollars more you can use romex and get rid of the old fire starters.
"Live Awesome!" - Kevin Carosa

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