2 prong out to 3 prong outlet????

Old 04-13-01, 02:58 PM
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I have an older home. I need to replace some of the 2 prongs to 3 prongs but there is no ground wires in the receptacles. I have a breaker box and it is grounded. Is there a way to do this w/o having to run grounding wires through my house? special outlet to buy?
Old 04-13-01, 03:21 PM
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First, find out if your boxes currently have a grounding connection. Use a voltmeter to check for voltage between the black wire and the metal electrical box. If you have 120 volts, you (probably) have grounding. I say probably because some knucklehead may have jumpered the neutral to ground in this or some other box, creating the false appearance of grounding.

If you do have grounding, then merely replace the two-prong receptacle with a three-prong receptacle, and jumper the receptacles grounding screw to a screw on the metal box. You may need to add such a screw to the box.

If you do not have grounding, the NEC allows you three choices:
(1) Replace the two-prong receptacle with another two-prong receptacle.
(2) Run a new grounding wire from this outlet back to the main panel.
(3) Add a GFCI receptacle somewhere on the circuit. Downstream from this outlet, you may install ungrounded 3-prong receptacles, if you label the receptacles with a label stating "No equipment ground".
Old 04-28-01, 01:14 AM
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Some "knucklehead" did exactly what you said in the rental property I just moved in to:

replaced two prong outlets with three prong outlets, jumpering the neutral to ground, giving the appearance of grounding. I have just a slim grasp on the grounding concept, but this certainly smelled fishy to me. Questions:

1. is this truly a "false appearance of ground", or does it create any advantage over not jumpering (granted that it is not proper)

2. Is there any increased potential for danger or problems, perhaps from the use of non-polarized 2 prong plugs, or recepticles with swapped hot and neutral wires?

SInce this work was done by my landlord's beloved handyman, I have to be diplomatic and absolutely correct in my facts. Please advise!
Old 04-28-01, 10:40 AM
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Hello Sunporch,

Let me start out by saying that I'm not a licensed electrician and there are many on here that are more knowledgeable in this field, but in my mind the practice of connecting neutral to equipment ground at the outlet is extremely dangerous. The recent long thread titled "grounding arguement" gets into many of the reasons that this is so, aside from the fact that it is a code violation. But, to me, there is one consideration that rises above all others, and I believe that this is also mentioned in the thread. Consider, if your neutral (white) is connected to equipment ground at the outlet, there are appliances of any kind that happen to be turned on plugged in to that circuit, the neutral wire opens up with a break or bad connection somewhere in that circuit. Any metal parts that would normally be grounded, any appliance cases that are tied to a third wire equipment ground, any of these things that are on the far side of the break are now floating at 120 volts above ground through the aforementioned plugged in and turned on appliance, whether a lamp, motor, or whatever. As you can see, this is potentially very dangerous indeed!
Old 04-28-01, 03:58 PM
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Spike made a good move referring you to the grounding argument post. Looks like someone even moved that post up to the forefront near this post for you.

Now just to take the energized metals of appliances caused by the jumping of white and bare or green wires a little bit further. Picture the white wire broken downstream of a load trying to start or run that is fed by this white/bare,green jumped circuit and you have any metal of a lamp, washer, or any other eletrical equipment on that same circuit. That one piece of equipment that is turned on but can't run because of that broken white wire down stream is looking for a path to ground. Now you or anyone else happens to be holding onto a grounded metal siding, water pipe, etc. Then you touch another piece of equipment to turn it on that is also on that circuit with the broken white wire downstream and a heavy load trying to find a path to ground so it can run. Guess what, you just became a conductor. You may never ever know it but the funeral parlor would stand a good chance of more business!

Hope this makes it clear how dagerous that little jumper cheat job is. May be easy cheap fix, but very likely may be lethal to you or a loved one.

Good Luck

Old 04-28-01, 08:05 PM
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Thanks for the replies on this and the other thread. I have a couple of questions that I will post on the other (grounding argument) thread. I would appreciate your further comments.

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