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Installing grounded 3-2 prong adapters

Posted by Reilly000 (My Page) on
Sat, Feb 16, 13 at 14:23

I am a student renting a room in an old house, which only has 2 pronged electrical outlets. I purchased a couple of 3 to 2 prong adapters so that I can use my computer and other things that have 3 prongs.

I have a question about the grounding loop on the adapter. Does it matter whether I insert the adapter into the top or bottom set of prong openings on the outlet? I ask because the adapter fits into both the top and the bottom set. But in order to use the bottom set and still utilize the grounding loop, the 3 prong openings on the adapter seem to be "upside down." The 2 prongs of the adapter do not seem to be polarized, which is why I can plug it in in this way (?) (I got it at Home Depot).

For what I am trying to do, I need to plug this adapter into the bottom prong opening on the electrical plate, and leave the top one free.

I would appreciate any help on this. I am only renting this room from an owner who has not maintained her home, and so my options are limited. Thanks so much. Reilly

This post was edited by Reilly000 on Sat, Feb 16, 13 at 15:05

Follow-Up Postings:

RE: Installing grounded 3-2 prong adapters

As far as electrical safety goes, those devices should NOT be allowed to exist. If you don't have a grounded receptacle it is extremely unlikely you have a viable ground to connect that thing to (the screw holding the cover plate on is not going to cut it).

As far as occupant protection goes, only a GFCI will suffice as a substitute. As for other uses of the ground pin on the plug (surge protection, RFI mitigation), you're not likely to get any benefit PERIOD.

So, the answer is you might as well just leave it disconnected.

RE: Installing grounded 3-2 prong adapters

The only certain value of the adapters is that it reduces the temptation to remove the grounding prong from the plugs. The grounding function is lost if the plug prong is removed even if the device is later plugged into a properly grounded receptacle.

RE: Installing grounded 3-2 prong adapters

It does not matter if you plug into the top or bottom receptacle. You will still not have an actual ground present.

RE: Installing grounded 3-2 prong adapters


It does matter which way you plug in the adapter. Find out which side of the existing receptacle is hot and line up the adapter for insertion with the narrower of the two blades engaging the hot. Remove the plate screw in the center, insert the adapter, and then screw through the loop in the adapter to the hole from which you withdrew it.

Straight forward questions such as yours are a pleasure to read.

RE: Installing grounded 3-2 prong adapters

IF the screw is actually grounded you will have a ground connection.

If the screw is floating (unconnected to a ground), you just have a way to put a 3-prong plug into a 2-prong receptacle and possibly create a safety hazard.

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