I totally agree with that last statement Drew and thanks.
My house, they cut the stinking ground wire so far back and the wire is stapled, so I can’t get enough slack to even ground it to the box.
wow…never mind…
Jim, it was nice to talk to you on the phone, hope you have a Merry Christmas my friend.
Thank you for calling.
The pleasure was mine Sir…Merry Christmas to You and Yours…
Opps …sorry Bob ,would have been a better response.
:mrgreen:I’ve heard plenty of guys call you worse Bob:mrgreen:
The system is grounded.
A three prong system simply allows for the additional grounding of individual devices that are plugged in to the system.
There is nothing “defective” about a two-prong system and, because there is nothing “defective” about it, it is still allowed by the latest versions of the NEC.
I never “write up” a two-prong electrical system for any other reason than to point out to the client that he will be limited as to the types of electrical devices that he can use in his house and that the use of a three prong adapter can create a hazard.
GFCIs do work as designed under this system.
IMO, it is insane to suggest to anyone that they should rewire an entire house because it has a two-prong system.
Thanks Jim and now more confusion.
If there is nothing wrong with the two prong system, why is it become a hazard when using the adapter?
For this simple reason, shouldn’t the electrical system then be upgraded?
The confusion comes from how we call out the different parts of the home wiring system.
The terms:
Hot
Neutral
Ground
http://www.school-for-champions.com/Science/images/ac_wiring-configuration.gif
Note that the in diagram the Neutral is tied to the Grounded conductor
Even without a Grounding conductor present in the home the system is still “grounded” at the POCO transformer.
The purpose of the the ground pin at the outlet in conjunction with the building grounding electrode is to provide a means safely removing leakage and fault currents that can appear on the metal shell of equipment when componets break down or components with voltage on the come in contact with case parts under fault or failure conditions.
For example: If the hot conductor came loose in side the equipment and came in contact with its metal case, there would be accessible 120 volts on the exterior of the equipment. If the case of the equipment is attached to the grounding system in a three wire system the ground wire will carry the fault current back to the panel and trip out the circuit breaker.
In a 2-wire system anyone touching the case of the equipment would be exposed to 120 volts and the current would flow through their body and back to “ground” (think bare feet on concrete floor or touching the water faucet at the same time) Because of the body’s internal resistance, not enough current would flow to trip the circuit breaker and the subject may experience serious injury or death.
No but it may be wise to add 3-wire outlets for use with computer equipment.
I agree Mike, and the point that I have been trying to make here is that in using my own house as an example, the 18 gauge ground wires are cut back and were never tied in to the metal box. So in this case, there is no ground at all.
Now in most house we see, unless you take the device out, you can’t tell.
So the point is, How should we call it?
Two prong receptacles were observed and recommend an upgrade or the system is ungrounded, or the system is grounded but not right.
Get my drift?:)
Is that disconnect 18 gauge connected at the service panel?
I’ll post a picture later Mike, thanks.
Marcel, you have no way of knowing if evey component of the electrical system is properly bonded to the grounding system without an evasive inspection. You can only report what you see and recommend accordingly. Using the example that we have been talking about all along, you need to say that the electrical system is grounded and the receptacles are of the non-grounding type. You can perform your CYA by making sure that every client knows that this is a non-invasive inspection ans you cannot see inside the walls, outlet boxes, ect.
OK, here is the mess I have. They should have fired this electician in the 60’s that wired my house.
If you look close, most of the grounds are 18 gauge and a lot of them are cut off.
Some of the grounds that are 12 or 14 gauge is added.
http://i373.photobucket.com/albums/oo171/mcyr/SDC11978.jpg
http://i373.photobucket.com/albums/oo171/mcyr/SDC11979.jpg
http://i373.photobucket.com/albums/oo171/mcyr/SDC11980.jpg
Comments;
Marcel,
The 2-wire outlets are not a problem unless you intend to plug something in that requires a 3-wire circuit like some computers, TVs, and some appliances etc.
I simply tell clients they may want to consider having an electrician install 3-wire outlets in the locations where they want to use this type of equipment.
Most table lamps are two wire and nothing is gained by plugging them into a 3-wire circuit.
Also, many laptops do not require a 3-wire circuit.
For example: If the hot conductor came loose in side the equipment and came in contact with its metal case, there would be accessible 120 volts on the exterior of the equipment. If the case of the equipment is attached to the grounding system in a three wire system the ground wire will carry the fault current back to the panel and trip out the circuit breaker.
I*n a 2-wire system anyone touching the case of the equipment would be exposed to 120 volts and the current would flow through their body and back to “ground” (think bare feet on concrete floor or touching the water faucet at the same time) Because of the body’s internal resistance, not enough current would flow to trip the circuit breaker and the **subject may experience serious injury or death. ***
Mike are you contradicting yourself?
Read it again.
One is the 2-wire example
The other is the 3-wire example.
Well luckily, when I set up my computer station, I was able to upgrade to a 12/2 with grounding set up.
The question is how should we note it in our reports when we see this in a home inspection?
Do we say that a two prong wiring system was observed and recommend an electrician to evaluate and walk away or should we say something different.
Since I am hearing that a two prong system is grounded that I don’t agree with due to the pictures I posted, it appears no matter what I would report is in error.
As with most dwellings, that have been sloppyly wired like mine, the outlets are most likely to not be grounded period.
Therefore, I believe we should note that there is a possibility that due to the two prong outlets observed, a grounded connection for the safety of the client might not be existing and an electrical contractor should evaluate.
That make sense?:)
That is pretty much why I have never worried about it in my own home, cause most of the outlets are being used by two prong fixtures.
I have upgrade a lot of them to a ground three prong where it needs to be.
Thanks Mike.