DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   2 Prong Electrical (http://www.diychatroom.com/f18/2-prong-electrical-19888/)

mjcongleton 04-13-2008 09:42 PM

2 Prong Electrical
 
I know this question has been asked many times, and I've read many answers on the subject, however I still have a few more specific questions for more specific situations.

I have a contract on a house which was built in 1953, all 2 prong outlets except for the kitchen and bathroom each of which has a grounded GFCI (metal grounding wire is present at outlet and fuse box area). All other outlets are 2 prong. I've checked the wiring at a couple outlets and small metal boxes are used and only a black and a white wire wrapped in what appears to be a non-metalic black caseing appears to be present. The electrical service to the house was updated in December 2007 to 200 amp service. I believe I can get the seller to pay reasonable fees to update the electric.

My questions are as follows:

How should I go about updating the electrical? It seems to me that I would need a ground wire running to each outlet in the kitchen and garage, and then I would have to have the 2 prong outlets replaced with 3 prong outlets. I say this because some kitchen appliances do not work well with GFCI (like refrigerators for example). As for the living room, and bedrooms, sunporch and bathroom, I figure I could ask to have the circuit breakers updated to GFCI breakers and then just replace the 2 prong outlets with 3 prong outlets. Only question on that one is this: Will I damage any of my electronics (computer, stereo, printers, ect...) if I don't have an equipment ground? I really don't think I or the seller wants the expense of running new wire throughout the house, but I also am not going to follow through with my contract if I can't make the electrical functional in the 2008 world.

One other question: If I understand everything correctly there are 3 wires in an electrical outlet: hot, neutral and ground, and in the end the neutral and ground end up connected and going into the ground; so why does a separate ground wire have to run throughout the house? Why weren't electrical outlets designed with the ground connected to the neutral at the box?

Thank you to those who read this entire (long) post. I appreciate your help in getting my house workable in the 2008 world.

chris75 04-13-2008 09:46 PM

Quote:

Originally Posted by mjcongleton (Post 116101)

One other question: If I understand everything correctly there are 3 wires in an electrical outlet: hot, neutral and ground, and in the end the neutral and ground end up connected and going into the ground; so why does a separate ground wire have to run throughout the house? Why weren't electrical outlets designed with the ground connected to the neutral at the box?

Nothing goes into the ground. :) Everything goes back to the source, (the transformer on the pole at the street)

J. V. 04-14-2008 09:47 AM

If you are not remodeling the house you are not required to upgrade the receptacles to three wire. GFCI's work with or without a ground wire (EGC).
You are correct that grounds and neutrals are connected in the main service panel. Neutrals are current carrying conductors. The EGC does not carry any current unless it is works as intended.

If you decide to ground the recepts you will need to pull new wire back to the panel. A ground rod is not sufficient. They must all go back to where they will actually provide protection.
So the question would be: Do I want to upgrade at a very substantial cost, or do I want to leave it as is. Either choice is acceptable.

jrclen 04-14-2008 10:57 AM

Lets see if I can explain things to help you decide what course you wish to take.

First a quick explanation of ground. Electricity does not wish to go into the ground or earth. It wants to return to where it came from. In this case, the transformer outside. The ground rods or other connections to the earth are for lightning strikes and high voltage surges only. Electricity will use the earth to get back to the transformer because the transformer is grounded also. That is why we can get electrocuted. I hope that is a little clearer than mud.

On a 120 volt circuit the neutral (grounded) conductor carries the electricity back to the source during normal conditions. Because there is current flow in the neutral conductor, we don't connect it to the frames of appliances nor to the cases of computers or drills. Instead, we connect a ground wire to these things. If a hot wire shorts to say the case of the computer, the ground wire carries that current back to the service panel. There, and only there, we place a bond (connection) between the ground wire and the neutral wire. So the electricity has a good, low impedance, (resistance) path back to it's source. That will cause the circuit breaker or fuse to open, and remove power from the faulty circuit.

Without that ground path, that computer case could sit there hot, until you touched it and became the ground. So you can add GFCI protection to that circuit which has no ground. With GFCI, you still have no ground, but if you touch that hot computer case, the GFCI will open the circuit before you receive a life threatening shock.

Under normal conditions that computer (or anything else) will not use, nor need that ground wire. Having it present is only for safety. The GFCI will also provide that safety.

I personally have no problem putting a refrigerator on a GFCI protected circuit. But many do not wish to do that. So without the GFCI protection, I would want a grounding wire. If the fridge shorted to it's frame you could receive a shock if you touched the fridge and say the sink or stove if they were grounded.

Now that you have an understanding of how things work, I hope you can better decide what you wish to do. Don't hesitate to ask more questions, there are lots of helpful experts here.

220/221 04-14-2008 11:13 AM

Forget rewiring.

Simply install GFCI breakers and change the receps to 3 prong.

You won't have a ground but you will be legally and realistically protected.


Quote:

Why weren't electrical outlets designed with the ground connected to the neutral at the box?


This is difficult for the novice to figure out because it requires an understanding of the circuit. If the neutral (white) connection fails between the receptical and the source (which it can and will do), the current from whatever is plugged in will try to find another path to "ground".

This could be thru the ground pin on something plugged in which is connected top the exposed metal parts. When you contact that metal, YOU may be the path to "ground".

Don't EVER do that.

mjcongleton 04-14-2008 12:12 PM

OK, Thanks for the good information. I think I'm going to go ahead and get the outlets in the Kitchen grounded since there seems to be conflicting reports as to how well a refrigerator will work on a GFCI. The rest of the house I will get breaker protection.

Are there any problems if outlets and lighting are on the same circuit with GFCI? I've heard people complain thay they set off the GFCI when they turn lights on.

Speaking of that, it looks like the new 2008 code states that certain rooms (bedrooms I think) need to have AFCI protection, so I'm wondering if I should try to get AFCI/GFCI breakers for the house? I've heard such breakers exist, but I don't know if I can get the house seller to pay what they might cost (I hear they are expensive). I figure, though, with 1953 wiring that I can't be too carefull.

Thanks for helping me out here. I am a novice and just want to make sure I'm getting everything right before I spend my hard earned money on a house.

220/221 04-14-2008 03:52 PM

It is a good idea to put a couple/few new circuits in the kitchen since this is your heavy usage area. Keep the refer off the GFCI just for logical reasons. Run the homerun to the refer and jump over to a counter top recep/GFCI outlet.

GFCI's don't seem to "nuisance trip anymore". In the 70's it seemed to be an issue.

jrclen 04-15-2008 08:58 AM

Quote:

Originally Posted by mjcongleton (Post 116243)
Are there any problems if outlets and lighting are on the same circuit with GFCI? I've heard people complain thay they set off the GFCI when they turn lights on.

I have seen no problems with lighting on GFCI. 221 is correct that nuisance tripping is a thing of the past. When a GFCI trips now, there is a good reason.

I have no experience with AFCI as my state does not require them, by code amendment. I will let someone else help you with that.

220/221 04-15-2008 03:45 PM

Quote:

I have no experience with AFCI as my state does not require them, by code amendment. I will let someone else help you with that.

Wait a few decades :yes:

jrclen 04-15-2008 10:01 PM

Quote:

Originally Posted by 220/221 (Post 116605)
Wait a few decades :yes:

I think they will include them with the 2008. We shall see. :whistling2:

handyman78 04-16-2008 08:59 AM

Quote:

Originally Posted by mjcongleton (Post 116243)
Are there any problems if outlets and lighting are on the same circuit with GFCI? I've heard people complain thay they set off the GFCI when they turn lights on.

No, but you might want to consider keeping these seperate just in case an outlet overload could leave you in the dark! I try to keep lighting and outlets on their own circuits for that reason. :wink:


All times are GMT -5. The time now is 02:31 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved