Home>Discussions>ELECTRICAL & LIGHTING>Changing two prong outlets to three prong?
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geffree
Changing two prong outlets to three prong?

Hello,

My 1950's house has some three prong outlets and some two prong. I want to change most of the two prong ones to three prong in an office and home entertainment area. The surge protectors and some of the equipment that I'm using say they need to be plugged into grounded outlets not the GFI kind.
What's the best way to change my two prong outlets to grounded three prong?

Thanks in advance.

Geffree.

jkirk
Re: Changing two prong outlets to three prong?

call and electrician

dj1
Re: Changing two prong outlets to three prong?

Changing two prong outlets into three prong outlets will merely enable you to plug in 3 prong wires without an adaptor. You still won't have grounding.

If you don't know enough about house wiring, jkirk is right: seek the help of a pro.

JLMCDANIEL
Re: Changing two prong outlets to three prong?

If there is a ground wire in the outlet, you would need to hook it up to the new receptacle. If there is no ground wire then a ground wire can be run to the box. It would also require that you check to make sure you have a ground wire from the panel buss to a ground electrode. You'll have to decide if you need an electrician or not.

Jack

geffree
Re: Changing two prong outlets to three prong?

Thanks for the replies.
It looks like there's no ground wire. Just two black and two white. Hooked up the new outlet and it seems to work great. A couple of follow-up questions:

What are the risks of plugging devices and surge protectors into this "un-grounded" outlet?

And how can I determine the load that this outlet can handle?

Thank you.

JLMCDANIEL
Re: Changing two prong outlets to three prong?

Look at the amperage rating of the breaker. Yes, the outlet works with no ground, it is not to code, and the surge suppressor will do you no good because it filters surges to ground but you don't have ground. Most electronic equipment need ground to filter noise so you may end up with noise on sound equipment and corrupted data in computers.

Jack

dj1
Re: Changing two prong outlets to three prong?

At this point may I suggest you contact 2 or 3 pro electricians and get estimates to ground all your outlets. Not a big job, but not cheap either.

You need this for your own protection and to protect all your expensive electronics.

Re: Changing two prong outlets to three prong?
geffree wrote:

What are the risks of plugging devices and surge protectors into this "un-grounded" outlet?

You may get yourself "LAMPED" a little bit.

Tom
Re: Changing two prong outlets to three prong?

The NEC does allow you to install a three prong GFCI in place of a two prong receptacle as long as you place the sticker on it that states "No equipment ground".

JLMCDANIEL
Re: Changing two prong outlets to three prong?
CaptTCB wrote:

The NEC does allow you to install a three prong GFCI in place of a two prong receptacle as long as you place the sticker on it that states "No equipment ground".

While this is permitted by NEC it still negates the function of surge suppressors.

Jack

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