# Changing 2 Prong To 3 Prong Outlet



## JAVAMAN

hi, I JUST RECENTLY BOUGHT A HOUSE. THERE IS ONE PLUG IN MY HOUSE THAT IS A 2 PRONG. I WANT TO UPDATE IT AND CHANGE IT TO A 3 PRONG SO THAT I CAN PLUS SOME MORE STUFF INTO IT. 

HOW DO I DO THIS AND IS IT AN EAISY PROCESS? PLEASE ANY HELP IS APPRECIATED, THANKS


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## J. V.

Remove the cover and pull out recepatacle. Do you have three wires or two wires. If you only have two wires you have an ungrounded receptacle. If the box is metal, you may have a jumper wire from the box to the receptacle, thats a good thing as you MAY have metalic path all the way back to the panel.

Regardless, just install the new receptacle and put in your own jumper, if the box is metal. It is totaly possible that you have a two wire cable that does not have a metal jacket. But, you have what you have. Install the new receptacle minus the ground wire.

white wire to silver terminal
black wire to dark colored terminal
bare wire to green terminal......If you have a bare wire.


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## jproffer

> It is totaly possible that you have a two wire cable that does not have a metal jacket. But, you have what you have. Install the new receptacle minus the ground wire.


   

Or maybe use a GFCI outlet in place of the 2 pronger. This still wouldn't be a grounded receptacle, but it would be code compliant.


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## Stubbie

> Regardless, just install the new receptacle and put in your own jumper, if the box is metal. It is totaly possible that you have a two wire cable that does not have a metal jacket. But, you have what you have. Install the new receptacle minus the ground wire.


J.V. 

You cannot just install a 3 prong grounding type receptacle in a metal box or any box for that matter that does not have a proven equipment ground wire back to the grounded conductor at the main panel. The installation as you explained is a code violation unless a proper equipment ground exists. It would serve no purpose to ground a three prong outlet to a metal box if the equipment ground isn't present in the branch circuit. Maybe I misunderstood what you are saying.
 
Acceptable means if a ground is not present in the box and you do not desire an equipment ground to facilitate the connection of electronics like computers or the added safety that a grounding wire provides. 










If the enclosure doesn't have a grounding means — for example, if the box contains old 2-wire NM cable without a ground — you can use a nongrounding type receptacle (*Fig. 1*). You have two other options as well. You can use a GFCI receptacle if you make sure it's marked “No Equipment Ground,” or you can use a grounding-type receptacle if it's GFCI-protected and marked “GFCI Protected” and “No Equipment Ground.”

If you desire a ground you can run a new circuit or Article 250.130 allows the following


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## bubs

If i neeed a eqiupment ground? can I use a self grounding receptical?


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## frenchelectrican

bubs said:


> If i neeed a eqiupment ground? can I use a self grounding receptical?


 
only way you can meet this critia [ sp ]

box is metal 
have estabed ground wire or steel emt or rigide pipe to the box.
if have green wire screwed to the metal box 

those 3 items it have to work before you can use the selfgrounded repectale.

[ also get a 2 wire neon tester to verify if you have a grounded box ]

Merci, Marc


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## tb582

Hi all, great thread- I have a similar issue, just bought a new (old) house. And yup most of the outlets are all 2 prong, I took the plate off of one of the old two prong outlets and here's what I can tell (with my limited knowledge.) 

There is a metal box, with a screw in the back of the box, the outlet it self has two wires. Also when we bought the house we had a professional electrican upgrade the service panel to 200 amp and he also ran a new grounding wire. So is it safe to assume that my metal boxes are all grounded properly, and that I can go ahead and install new 3 prong outlets? I picked up one of these the other day and I'm anexous to give it a try. http://www.smarthome.com/4536W/Acenti-15-Amp-Duplex-Receptacle-Alabaster-AC215-W/p.aspx

I was digging around in my tool box and found a neon tester, I'm must admit I'm a bit afraid to try it though . It doesn't have two prongs where I can stick one in the outlet, it consists of two jaw arms/clamps. Is this still OK to use? Just clamp the red wire onto the HOT wire in the box and the other to??


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## darren

Just because your main panel is grounded does not mean your boxes are bonded to the ground. If it is an older house not useing emt or older style armoured cable then your box will not be grounded. Your best solution is to find the first outlet after the panel and put the GFI there and then you can put regular plugs the rest of they way with the "no equipment ground" stickers.

I have to use the GFI method in my house as well, but i am going to put the GFI next to panel and then continue the circuit on as normal. This way I won't have to run around trying to find the first plug in the line.

If you run into a 3 wire when doing this come back here for some advice, you can't put a GFI on the beginning of a multiwire branch ciruit(i.e share the neutral)


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## 220/221

Use GFCI receps or breakers.

If your panel will accept GFCI breakers and there are no 3 wire home runs, that's the way to go as the entire circuit is protected and you can change all the receps.


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## tb582

Thanks for the quick replies....I'm very new to all of this. 

I dont like the idea of having every outlet be GFIC although I'm not sure why. I guess I just assumed that they are mainly for areas that are close to water etc....

Now that you mention it the electrician did put a GFI oulet right below the new 200 amp electric panel. So that being the case am I able to just install the outlets that I had posted?


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## 220/221

> I guess I just assumed that they are mainly for areas that are close to water etc....


Forget the _water_ thing. 

A GFCI is a safety thing and will "take the place" of a ground wire. Don't make me explain it, just trust me :laughing:


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## tb582

220/221 said:


> A GFCI is a safety thing and will "take the place" of a ground wire. Don't make me explain it, just trust me :laughing:


OK  but given the fact that the electrician did install a GFI outlet right beneath the electric panel, can I not just install regular 3 prong plugs now as Darren suggested? 



darren said:


> Your best solution is to find the first outlet after the panel and put the GFI there and then you can put regular plugs the rest of they way with the "no equipment ground" stickers.
> 
> I have to use the GFI method in my house as well, but i am going to put the GFI next to panel and then continue the circuit on as normal. This way I won't have to run around trying to find the first plug in the line.
> 
> If you run into a 3 wire when doing this come back here for some advice, you can't put a GFI on the beginning of a multiwire branch ciruit(i.e share the neutral)


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## darren

No you can not, the GFI he installed below the panel is a conveniance plug that is probably on its own circuit.

Each circuit needs a GFI at the beginning of the run, if you have 4 circuits of plugs you want to change out you will need 4 GFI.


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## tb582

darren said:


> No you can not, the GFI he installed below the panel is a conveniance plug that is probably on its own circuit.
> 
> Each circuit needs a GFI at the beginning of the run, if you have 4 circuits of plugs you want to change out you will need 4 GFI.




ahhh I gotacha... how does one go about finding the first plug in the circut?

Is there a way to check and see if the metal box is grounded properly, so I can bypass all this and just install regular 3prong oulets?


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## mpoulton

tb582 said:


> ahhh I gotacha... how does one go about finding the first plug in the circut?
> 
> Is there a way to check and see if the metal box is grounded properly, so I can bypass all this and just install regular 3prong oulets?


Turn off the breaker for that circuit. Check for continuity between the neutral wire in the box and the metal box itself. You should read essentially no resistance (same reading as with your test leads shorted together). If that is the case, then look to confirm what the grounding path is: Is the box installed with metal conduit? Is it fed with metal-sheathed cable? Is there a grounding wire connected to the box? Any of those things would be fine. If you can't tell how it's grounded, don't trust it and install a GFCI instead.


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## J. V.

This thread must be over a year old. I should have not told the OP to do, what I would have done in my house.


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## tb582

mpoulton said:


> Turn off the breaker for that circuit. Check for continuity between the neutral wire in the box and the metal box itself. You should read essentially no resistance (same reading as with your test leads shorted together). If that is the case, then look to confirm what the grounding path is: Is the box installed with metal conduit? Is it fed with metal-sheathed cable? Is there a grounding wire connected to the box? Any of those things would be fine. If you can't tell how it's grounded, don't trust it and install a GFCI instead.


Forgive me but what type of meter should I be using to test this?


and as far as i can tell there is a screw that is located in the back of the box towards the top, and I can see a metal wire attached to it. I would still like to have a way to verify that its grounded properly


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## mpoulton

tb582 said:


> Forgive me but what type of meter should I be using to test this?
> 
> 
> and as far as i can tell there is a screw that is located in the back of the box towards the top, and I can see a metal wire attached to it. I would still like to have a way to verify that its grounded properly


A resistance/continuity/ohm meter. Almost all multimeters do this.


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## 220/221

> This thread must be over a year old. I should have not told the OP to do, what I would have done in my house.


tb582 has turned it into his thread :thumbup:




> Is there a way to check and see if the metal box is grounded properly, so I can bypass all this and just install regular 3prong oulets?


It's electrical 101 but you need an understanding of how electricity flows thru a simple circuit.

With a voltage tester, check hot to neutral (black to white) and you will have 120 volts. Then check hot to the metal box. If you have 120v, you have some kind of a ground. If you have metal jacketed cable, it may or may not be an *approved* ground. If you have old non metallic jacketed cable you will see the bare ground wires in the box (99% of the time)



> and as far as i can tell there is a screw that is located in the back of the box towards the top, and I can see a metal wire attached to it. I would still like to have a way to verify that its grounded properly


I missed this. Take a pic to be sure but it sounds like you have a ground wire in there. For a short period in the late 50's/early 60's, they started using grounded cable and ground the box but still use 2 prong receps.


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## tb582

220/221 said:


> tb582 has turned it into his thread :thumbup:
> 
> Take a pic to be sure but it sounds like you have a ground wire in there. For a short period in the late 50's/early 60's, they started using grounded cable and ground the box but still use 2 prong receps.


I took pics this morning but forgot the memory card on my desk - I'll post pics later on. Hopefully we can solve this


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## tb582

220/221 said:


> tb582 has turned it into his thread :thumbup:
> 
> 
> 
> 
> It's electrical 101 but you need an understanding of how electricity flows thru a simple circuit.
> 
> With a voltage tester, check hot to neutral (black to white) and you will have 120 volts. Then check hot to the metal box. If you have 120v, you have some kind of a ground. If you have metal jacketed cable, it may or may not be an *approved* ground. If you have old non metallic jacketed cable you will see the bare ground wires in the box (99% of the time)
> 
> 
> 
> I missed this. Take a pic to be sure but it sounds like you have a ground wire in there. For a short period in the late 50's/early 60's, they started using grounded cable and ground the box but still use 2 prong receps.


Pics attached, hopefully I can just install std. 3prong outlets


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## 220/221

You do have grounded cable. 

Test from hot to ground to make sure the ground is complete.


Turn off power. Test to make sure it's off.:jester:


1. Remove the screws and clamps from the box. Removing the clamps will make more room. It's a _technical_ violation but the cable is not going to magically get pulled out of the box at this point.

2. Install a ground screw (or the existing screw) in one hole and wrap the ground wire around it clockwise to effectively ground the box.

3. Install a short (appx 5") bare or green pigtail with a ground screw (or existing screw) in the other hole using the same method.

4. Install your new recep using the screw terminals rather than the back stabs amd making sure that the bare wire doesn't end up touching the side screw terminals.


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## tb582

220/221 said:


> You do have grounded cable.
> 
> Test from hot to ground to make sure the ground is complete.
> 
> 
> Turn off power. Test to make sure it's off.:jester:
> 
> 
> 1. Remove the screws and clamps from the box. Removing the clamps will make more room. It's a _technical_ violation but the cable is not going to magically get pulled out of the box at this point.
> 
> 2. Install a ground screw (or the existing screw) in one hole and wrap the ground wire around it clockwise to effectively ground the box.
> 
> 3. Install a short (appx 5") bare or green pigtail with a ground screw (or existing screw) in the other hole using the same method.
> 
> 4. Install your new recep using the screw terminals rather than the back stabs amd making sure that the bare wire doesn't end up touching the side screw terminals.



Great I'm going to try to either find my voltmeter or pick one up tomorrow. I'm assuming it will say in the directions for the meter, but does the red prob touch to the HOT wire and the black prob to the screw in the back to test for ground?


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## 220/221

Doesn't matter.


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## tb582

tb582 said:


> Great I'm going to try to either find my voltmeter or pick one up tomorrow. I'm assuming it will say in the directions for the meter, but does the red prob touch to the HOT wire and the black prob to the screw in the back to test for ground?



OK tonight is the night I shall verify if the boxes are grounded, this is the meter I have: http://www.homedepot.com/Electrical...splay?langId=-1&storeId=10051&catalogId=10053

However the directions are less than helpful. What should I have the dial set to?

The I simply just touch one end to the hot wire and the other to the screw in the back, correct? and all this while the electricity is still on


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## 220/221

Set meter to "AC volts"

One lead on *black*, one lead on *white* will read appx *120 *volts.

One lead on *black*, one lead on *ground* (or anywhere on the metal box) should read appx *120* volts.

*White* to *ground* should read appx *zero* volts.


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## tb582

220/221 said:


> Set meter to "AC volts"
> 
> One lead on *black*, one lead on *white* will read appx *120 *volts.
> 
> One lead on *black*, one lead on *ground* (or anywhere on the metal box) should read appx *120* volts.
> 
> *White* to *ground* should read appx *zero* volts.



So I'm going on the left side of the meter what do I set the dial to 200? the little audio tone?


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## tb582

220/221 said:


> Set meter to "AC volts"
> 
> One lead on *black*, one lead on *white* will read appx *120 *volts.
> 
> One lead on *black*, one lead on *ground* (or anywhere on the metal box) should read appx *120* volts.
> 
> *White* to *ground* should read appx *zero* volts.



YUP :thumbup: thats exactly what they read!

Can you shed a bit more light on this?




220/221 said:


> 1. Remove the screws and clamps from the box. Removing the clamps will make more room. It's a _technical_ violation but the cable is not going to magically get pulled out of the box at this point.
> 
> 2. Install a ground screw (or the existing screw) in one hole and wrap the ground wire around it clockwise to effectively ground the box.
> 
> 3. Install a short (appx 5") bare or green pigtail with a ground screw (or existing screw) in the other hole using the same method.
> 
> 4. Install your new recep using the screw terminals rather than the back stabs amd making sure that the bare wire doesn't end up touching the side screw terminals. .


I'm going to remove the old outlet - Use my new outlet and connect both the white and black wires to the same connectors as they are on in the current setup. I then need to run a small piece of wire from the new outlet's ground screw (which is on the lower side of the outlet) to the grounding screw in the back, correct?

Where do I get this "bare or green pigtail wire? Can you link to it on homedepot's website?


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## tb582

tb582 said:


> Can you shed a bit more light on this?
> 
> I'm going to remove the old outlet - Use my new outlet and connect both the white and black wires to the same connectors as they are on in the current setup. I then need to run a small piece of wire from the new outlet's ground screw (which is on the lower side of the outlet) to the grounding screw in the back, correct?
> 
> Where do I get this "bare or green pigtail wire? Can you link to it on homedepot's website?


Anyone?


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## Leah Frances

tb582 said:


> Anyone?


You don't need someone to post a link to HD for you. Maybe you're thinking too hard about this...

The quickest thing, if you have some same gauge wire around, is to strip a convenient length bare. 

At HD (or where ever) you can buy pre-cut lengths of green ground wire, or you can buy off the spool in whatever length you need.


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## Scuba_Dave

HD does have the pigtails, just check the electric aisle
I usually just use scrap wire that I have hanging around


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## COLDIRON

*I did it*



Stubbie said:


> J.V.
> 
> You cannot just install a 3 prong grounding type receptacle in a metal box or any box for that matter that does not have a proven equipment ground wire back to the grounded conductor at the main panel. The installation as you explained is a code violation unless a proper equipment ground exists. It would serve no purpose to ground a three prong outlet to a metal box if the equipment ground isn't present in the branch circuit. Maybe I misunderstood what you are saying.
> 
> Acceptable means if a ground is not present in the box and you do not desire an equipment ground to facilitate the connection of electronics like computers or the added safety that a grounding wire provides.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> If the enclosure doesn't have a grounding means — for example, if the box contains old 2-wire NM cable without a ground — you can use a nongrounding type receptacle (*Fig. 1*). You have two other options as well. You can use a GFCI receptacle if you make sure it's marked “No Equipment Ground,” or you can use a grounding-type receptacle if it's GFCI-protected and marked “GFCI Protected” and “No Equipment Ground.”
> 
> If you desire a ground you can run a new circuit or Article 250.130 allows the following


 I did it several years ago when my daughter purchased a house, well guess what?? when she sold it it failed electrical every one had to be removed and the two wire outlets reinstalled. Of course we had to by new ones. Oh well live and learn.


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## Wildie

SULTINI said:


> I did it several years ago when my daughter purchased a house, well guess what?? when she sold it it failed electrical every one had to be removed and the two wire outlets reinstalled. Of course we had to by new ones. Oh well live and learn.


 Here in Ontario Canada, I was required to install Uground recepts in a house with knob and tube wiring!
I ran green/stranded #14 back to a water pipe ground, at the behest of the electrical inspector.
This was rental property and a law was brought in stating that rental properties were to be provided with U grounds.
This was before GFCI recepts became available!


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## tb582

Just wanted to say thanks to everyone who has helped me out on this thread  - Replacing the outlets is going slow but going....

Quick question - I came to one outlet last night that for some reason had two black and two white wires both connected to the outlet... I wasn't sure why this was, and verified that no wall switch controlled the outlet that I could find anyway.... so I tried hooking it up with just the one hot black and one ground white wire and no dice. Only once I hooked it up as it was 2B 2W did the outlet work.


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## AllanJ

tb582 said:


> two black and two white wires both connected to the outlet...


Power comes to that outlet box and daisy chains from there to another outlet box. The first time you reconnected it with one black and one white you connected the downstream part of the circuit leaving the power feed unconnected.


> I usually just use scrap wire that I have hanging around


Don't forget to tell the newbies that ground pigtails must be bare or green, neutral pigtails must be white, and hot pigtails must be some other color (black and red being most common).


Stubbie said:


> ... (picture, q.v. pp 1) ...


Did I see in the picture a ground wire for the previously ungrounded receptacle brought out to the surface and run exposed along baseboards and up and around doorways and down to the panel more or less following the route of that receptacle's wiring inside the wall? In another thread (or was it some other forum) I commented about this method to avoid fishing or cutting open the wall and a comment in reply said that I was improper.


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## tb582

AllanJ said:


> Don't forget to tell the newbies that ground pigtails must be bare or green, neutral pigtails must be white, and hot pigtails must be some other color (black and red being most common).


Hey who you callin a newbie :laughing: but seriously thought I did figure that the neutral wire had to be green.


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## srusten

*Replacing Two wire Outlet with Grounded Three Prong*

You guys are confusing me with your responses to this question. Here's what I need clarified. I have a Two Wire Outlet in a Metal Box that has BX to a Junction Box in my Basement that is connected to the Panel of Course. Also connected to the Junction Box is another Grounded Outlet or Three Prong connected with Three Wire Romex. I want to change the Two Wire outlet with the BX to accommodate a Grounded Outlet and as I see it ALL I need to do is just snip a piece of copper ground wire and connect it to a screw in the metal box and from there to the Ground screw on the new Outlet and the other two wires, Hot to the Brass Screw, White Ground to the Silver and it's a Done Deal. Am I right or wrong? The other question I would ask is that I have this older cloth or whatever it is covered wire running from this Junction Box to the Panel. If indeed that does have a Copper ground is it OK to keep that or should I just go ahead and replace that with new Three Wife Romex?


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## darren

This post is two years old you should start a new post, you will will get more responses.


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## madmaxx25

Great read!

dominick moresco


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