My new house has 2 wire ungrounded receptacles in most of the rooms. I want
to upgrade to grounded "3 prong" receptacles.
Since removing the old (#14-2) AC wiring and replacing it is not an option I
thought I could do it by running a bare #12 copper wire down to the
crawlspace under the house, bussing all the wires together and ending at a
earth ground spike and a cross tie to the main breaker box.
This should work but is it to code in California? DOes it need to be
inspected? Is there any reason this would be unsafe? Should I use
Insulated wire instead so the conductor never touches the structure (wood)?
I just wanted some assurance before I bust by butt under the house.
Do you mean "Type AC" AKA "BX". a spiral wrapped steel armored cable???
If so you already have a grounding path.
That is certainly an option although it might not be a california legal option.
You can also skip the ground rod (assuming your existing panel is properly
grounded). Install your bus and connect it to the grounding bus in the panel
with a #4 or a #8 in a raceway. (#4 typically does not ned physical protection)
The main issue I see is protecting everything from damage, environmental and
physical. This is one of those cases where the increase in safety is worth a
It is probably a waste of time to upgrade the receptacles that will never see a
3 prong plug too. GFCI (the other way to install 3 prongs) is actually safer
when you don't have a grounded case appliance.
By AC I meant alternating current
4 gague wire!!! how much current do you think this ground path to see. I
was planning to use 12 gague bare wire everywhere all the way up to the
panel. Did I get you wrong?
GFCI gets me part of the way there but as you say it still does not offetr
the same protection as a seperate ground on appliances so equipped.
The only reason I said 4 ga is an inspector would not require some kind of
physical protection for #4. (based on the GEC rule)
Actually a #6 Equipment Grounding Conductor can be run without physical
protection. 250.120(c) when they are not in the wall cavity. In the cavity your
#12 is OK. That is the main issue. You are right that for 15 and 20a circuits
12ga is fine based on ampacity. The only problem is, it is supposed to be
protected in the jacket of your Romex. YMMV on how an inspector would feel
about bare or green insulated #12s running around in the crawl space.
Green insulated is probably what you are going to end up using since that is
what they sell.. Usually #8 is the smallest "bare" you will find.
Personally I wouldn't fail you if the #12 was neatly stapled and closely
followed the floor joists. I would only worry about places where someone might
grab it and break it.
Since your new add on Equipment Grounding Conductors (EGCs) will not be
run with the circuit conductors the impedance of the fault current path
will be much higher than if they were. I would suggest that you add
Ground Fault Circuit Interrupter (GFCI) protection to the circuits in
addition to the retrofit EGCs. That way when a fault occurs your
retrofit EGC will carry enough current to trip the GFCI thus clearing
the fault prior to contact by humans.
First, external ground wires must be green insulated as, if
I remember correctly, code demands that green insulation.
Second, ground receptacles to the single point safety ground
located in breaker box panel. Receptacles provide a safety
ground (not earth ground) which is why the ground wire must
make a connection directly to the same bus bar used by white
neutral wires (inside breaker box). This connection cannot be
made indirectly via the ground rod. In fact, grounding
directly to the ground rod would be a code violation.
Third, box must be earthed typically by a bare 6 AWG solid
copper wire. This connection from breaker box to earth serves
multiple purposes. Code only requires a breaker box be
earthed to a nearby ground rod for human safety reasons. And
code specifically demands a dedicated earth ground rod or
equivalent. That earthing wire also must be less than 10
feet, with no sharp bends or splices, for another reasons
beyond scope of the code - transistor safety.
Four, any circuit that cannot be safety grounded can provide
human safety using a GFCI. A specific three word phrase must
be printed on every three prong outlet that only uses GFCI for
human protection. One reason is that some electrical
equipment may not work correctly (and some interconnected
electronics may be damaged) if the safety ground is not
Five, this and other grounding explained by volts500 in the
newsgroup alt.home.repair entitled "Grounding Rod Info" on
12 July 2003 or at:
So you think many outlets cannot be safety grounded? Be
amazed how easily a good electrician can wire a safety ground
without much damage. You pay them big bucks because they have
those special tools and abilities.
In simple terms, every bathroom, kitchen, heavy appliance,
and interconnected electronic appliances (if any uses a three
prong outlets) should have the third prong safety ground - not
just a GFCI. Other electrical consumers would be just fine on
a two prong connection. That requirement would substantially
reduce complications and use the professional electrician only
where he is really required.
.> First, external ground wires must be green insulated as, if
250.119 Identification of Equipment Grounding Conductors.
Unless required elsewhere in this Code, equipment grounding conductors shall be
permitted to be bare, covered, or insulated. Individually covered or insulated
equipment grounding conductors shall have a continuous outer finish that is
either green or green with one or more yellow stripes except as permitted in
The only place where whites and grounds can connect is in the service
disconnect enclosure. That may NOT be the main breaker panel. You could have a
service disconnect in the meter base or some other place outside. That is where
the main bonding jumper is and the only place where grounds and neutrals can
You will still have a single point ground if this is true, even if you don't
home run every grounding conductor. That is really only a surge protection
issue, not a safety one. As long as you have a sufficient fault current path
back to the main bonding jumper you will still trip a breaker on a fault. The
NEC addresses parallel neutral paths but they don't care about ground loops on
the EGC. You have them all over if you have a metal piping system. (water
heaters, disposals, pumps, gas furnaces etc)
Red is hot here too. The one that will bite you is blue, that is a phase too
typically phase C on a 208/240 3 phase.
(except for those international line cords)
480 3 phase uses brown/orange/yellow.
The 277 L/N on a 480 wye will be violet phase and grey neutral. It was never
really legal to use grey but everyone did it so they finally fixed the code.
I guess it is color codes that makes the electrical trade safe from foreign
The only place we will see light blue neutrals is in line cords, mostly because
they are sold internationally but even that sounds silly to me, since the only
folks who use NEMA plugs are the US and Japan. I guess we blew up all the
original Japanese plugs in 1945.
The green/yellow does seem pretty universal. The only other choice here is
solid green or bare so it isn't that confusing. The only place you usually see
bare wire is in a cable or in large sizes
(3.7mm - 5.89mm dia) #8, 6, 4 AWG.
I guess we should all put a country in our taglines to avoid confusion. We
don't even agree with Canada on a lot of things electrical. (politics or beer)
I bet you even have round footballs ;-)
Light blue neutrals seems to be a European invention - the system I'm
thinking of was 440V Red/White/Dark Blue with light blue neutral. At least
*all* the neutrals were the same colour! It's the only time I've seen such
a thing - it's black over here.
Actually, even you guys can't make up your minds - a couple of ABS-certified
ships I've seen over here use black neutrals.
Now *that's* a good idea!! :-) Sorry ... our footballs are larger than
Those boat guys have made up their own rules for centuries. That's probably why
the NEC (NFPA) never wanted to have anything to do with them or vice versa.
The NEC actually started as one page in the 1898(?) New York City fire code
and now NYC doesn't even follow the NEC. There is a lot of politics in the NEC
and a pretty good chunk of greed. It is a copyrighted document that sells for
close to $100 in paperback. You won't see it published for free anywhere in
spite of the fact that it has the force of law in most communities.
Electrical professionals have a love/hate relationship with our code.
On 05 Dec 2003 07:08:45 GMT, email@example.com (Greg) wrote:
Actually I just had a Mike Holt class on grounding and bonding
yesterday Dec 4. He mentioned NYC gave up their document and had just
adopted the 1999 NEC within the last couple of months.
Washington State Resident
Registered Linux User # 312991
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