Can you please explain in details why one is better than the other and why? thanks.
2007-03-11 06:11:49 · 6 answers · asked by Anonymous in Home & Garden ➔ Maintenance & Repairs
In the USA
The quality of the earth connection depends on the surface area of the ground electrode in direct contact with the soil. The soil should be firm, not loose like sand. A 3/4" metal water pipe has more surface area than a 5/8" ground rod.
A metal water pipe more than 10 feet long underground is an excellent ground electrode. The problem is, many water companies are replacing the metal pipes with plastic. When that happens, the ground is lost. Also, meters and valves inside the house can be replaced with who knows what, and the ground is compromised.
Ground rods are okay. When driven into loose soil, the rod does not make a firm contact with the soil, and is not as good as driven in firm soil.
The 2005 National Electric Code requires that you bond your electric service to a metal water pipe if it exists. The code further requires that you provide at least one ground rod. If you have less than 25 ohms to ground at the ground rod, then you are required to provide a second ground rod.
However, if the building footing contains at least 20 linear feet of minimum 1/2" diameter rebar, and the rebar was used as the ground electrode, you do not need to provide any ground rods, but you do have to bond the metal water pipe.
Ground rods generally are 5/8" diameter, 8 feet long. A metal water pipe underground is at least 3/4" diameter, and probably more than 8 feet long. The more metal there is in contact with the earth, the better the ground. Rebar in a footing is better than ground rods or water pipe. A metal water pipe is better than a ground rod.
If you need to provide a good earth ground for computers or sensitive electronic equipment, and you cannot connect to rebar in a footing, consider driving several ground rods, at least six feet apart, and run a continuous ground conductor from the service entrance equipment to the rods, connecting to them all.
2007-03-11 07:26:59 · answer #1 · answered by Dave 5 · 3⤊ 0⤋
That depends on where you live. In Arizona, where it is a dessert, the sand at surface level where copper is buried gets very dry, thus it will not act as a very good ground and will fail the conductance test required by State code.
So a ground rod driven deep into the soil will penetrate moist area to a better extent and will almost always pass the State code here in Arizona.
It is the moisture in the soil which enhances the grounding effects of ground rods as well as the mineral conducting components of the soil.
I would not be overly concerned about ground rods, the entire electrical grid in the State is grounded in so many places and so deeply that it is a mere perecaution to use a ground rod on your home residence. Take a look at the electric pole near you and even there youl see a ground wire running deeply into the ground along the deep buried pole.
Dont be fearful, that ground rod there or not, will not save your life from any shocks or anything like that. Your system in the house is attached to the state wide grounding at millions of locations around.
2007-03-11 08:55:57 · answer #2 · answered by James M 6 · 0⤊ 0⤋
Ground rods are the only safe way to ground an electrical system and some localities even require you to have 2 normally involving running a continuous wire (no splices) to the panel. Water lines have too many factors that can negate the ground path. Dissimilar materials, cutting the line, sleeving and encasement issues, etc. can cause a water line to not provide a dependable ground. Plus you could light up all your metal plumbing fixtures if a grounding situation is present. Rods are easy to install unless you are in an extremely rocky area and provide the only sure ground.
Good Luck!
2007-03-11 07:00:02 · answer #3 · answered by Pat C 3 · 3⤊ 0⤋
NEVER EVER ground you gas pipe. That is a direct code violation. Run a wire from your copper water pipe to your service and tie into the ground bar. If your service feeder wires are size 2 or smaller use a #8, if they are 1 or 1/0 use #6 if 2/0 or 3/0 use #4 size wire. that's per NEC Code 250.66
2016-03-18 04:32:39 · answer #4 · answered by Ellen 3 · 0⤊ 0⤋
grounding to a pipe is o.k. until the pipes are uncoupled. for instance if the water co. pulls the meter, when the house is vacant or if repairs are needed. also, if there is a miswired component in your electrical system you could inadvertantly electrify your plumbing.
2007-03-11 06:20:23 · answer #5 · answered by sic-n-tired 3 · 0⤊ 0⤋
a ground rod is better for grounding
you are supposed to ground your water lines not use them for a ground.
2007-03-11 06:16:25 · answer #6 · answered by Norman K 2 · 1⤊ 0⤋