control boards in modern appliances

[AZ Nomad]

Time to put the arc welder on it's own circuit.

[snotty]

westom formerly posted for many years as w_tom. He's a grade-A usenet nutball who only posts about surge suppressors. Sometimes his advice is "a little off", and sometimes it is potentially fatal. Believe anything he tells you at your own peril.

[bud--]

I really don't understand where this nonsense comes from.

The NEC *requires* that a water service pipe, if it is at least 10 ft of metal in the earth, be used as an earthing electrode. It has been a requirement since 1777 (more or less). Also bonding is required across the water meter.

Rules have changed somewhat, including now the connection to the water service pipe must be within 5 feet of where the pipe enters the building.

For over 50 years the NEC has required a "supplemental" electrode for water pipe electrodes *if* the water service pipe was likely to be replaced by plastic. Years ago the code was changed to just routinely require a "supplemental" electrode. Ground rods were routinely used. The NEC requires the resistance to earth for a ground rod be 25 ohms or less, or else 2 rods can be used. It is easiest to just install 2 rods. Ground rods are a poor earthing electrode (25 ohms is slightly better than nothing). A metal water service pipe is a good electrode, particularly if connected to a metal municipal water system. The code now requires, for most new construction, a "concrete encased electrode", commonly called a Ufer ground, be an earthing electrode. This is a good electrode, and replaces the ground rod(s) as a supplemental electrode when needed.

Only if the water service pipe is not metal does the NEC require

*bonding* of the interior water pipe (instead of using the service pipe as an earthing electrode). The rules are similar, but not identical, to use as an earthing electrode. ************** In addition to checking the earthing system, I would check the neutral-ground bond, which should be at the service disconnect. If it is not present, the hot and neutral wire potential could rise far above the ground wire, which in some cases cause damage. The bond is often a screw that looks like a mounting screw for the neutral bar. Recent ones are likely green.

[salty]

Please consult with the building department inspector in any city in the U.S.

Grounding your electrical system via the water service pipe alone does not meet code anywhere that I have ever heard of. Yes, you must bond the water service pipe to the electrical system for safety, but a separate earth ground for the system is ALWAYS required to meet code.

[hallerb]

manufacturers love control boards since they let the manufacturer decide when any products end of life is.

many can work around mechanical stuff but a dead board thats no longer made is the end of that device....

[HeyBub]

Think open neutral - at your house or a neighbors on the same transformer.

[Percival P. Cassidy]

I assume that you mean "1977": I can't imagine that the NEC existed in 1777.

But I think you and HeyBub are talking about two different things. Yes, IF there is a metal water pipe with at least ten feet in the ground it must be used as one element of the grounding system -- but always supplemented by at least one ground rod (two to avoid having to prove that the first one has no more than 25 Ohms resistance).

BUT if there is metal plumbing but the supply line is not metal with at least ten feet in the ground, then that metal plumbing must be bonded to the electrical system ground so that the plumber does not get electrocuted by an accidentally live water pipe. Ours isn't, as far as I can tell.

Similarly, gas piping must be bonded to the electrical system ground for the same reason. Ours isn't, as far as I can tell.

Perce

[Stormin Mormon]

Years ago, when the water department put in plastic meters, they had to put a large metal strap from one side to the other. Other than that, metal plumbing pipes are supposed to be grounded, unless there is a bit of plastic pipe in there some where.

[Stormin Mormon]

My dead canary sings opera. It's a real tweat to hear. Even the transients like to come and loiter outside my window. I put up a "no loitering" sign, and now they just stand around.

[Stormin Mormon]

The Continental Congress must have been rather busy that year. The

1777 congress also mandated airbags in passenger cars, and 1.6 GPF toilets. In addition to writing much of the Bill of Rights.

[bud--]

Please consult with the National Electrical Code "250.50 Grounding Electrode System. All grounding electrodes as described in 250.52(A)(1) through (A)(7) that are present at each building or structure served shall be bonded together to form the grounding electrode system."

"250.52(A)(1) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth for 3.0 m (10 ft) or more...."

A water pipe in the ground for 10 ft (described by 250.52(A)(1)) MUST be used as a grounding electrode (by 250.50).

This has been in the NEC far longer than any of the code books I have (oldest one is 1968). I think it goes back to 1777 - one of the first things the Continental Congress did

It meets the code in my house. It was code compliant when installed so it is compliant now. That probably applies to millions of houses.

As I wrote, bonding rules are different. You only "bond" if the water service pipe is not used as a grounding electrode. See above - if a metal pipe is 10 ft in the earth it is *REQUIRED* to be used as a grounding electrode.

Don't confuse bonding with use as a grounding electrode.

A "supplemental" electrode was not *always* required until the 1978 NEC.

It is "supplemental" because it supplements the main electrode - the water pipe. Ground rods were commonly used - they are close to a joke. A water pipe is far better.

My house had the service upgraded before 1978 and does not have a "supplemental" electrode. It is code compliant.

The NEC Handbook says "The requirement to supplement the metal water pipe is based on the practice of using plastic pipe for replacement when the original metal water pipe fails." Water pipe is a good electrode. The problem is it may be replaced by plastic in the future.

Contrary to what seems to be a common internet opinion, water pipe (metal, 10 ft...) is *REQUIRED* to be a grounding electrode. Read the NEC (relevant quotes provided).

[salty]

You are misunderstanding what you are reading, Bud. Please don't become another w_tom. One is enough!

[bud--]

Perhaps you could explain.

The relevant code was provided and is perfectly clear. If it meets the description in 250.52(A)(1) (10 ft metal in the ground) it MUST be used as an earthing electrode (250.50).

One of w_tom, aka westom's, rants was that not only was a water service pipe not required to be used as a earthing electrode, it must absolutely not be used as an earthing electrode. One of his most bizarre posts was on the subject.

[salty]

But cannot be used as the SOLE earthing electrode. For good reason.

Sort of along the lines of the automobile inspections they used to require in my state when you registered an older vehicle...

You were not required to have glass in the side windows, but if you did, it could not be cracked. I got a pickup truck with a cracked side window through inspection by rolling it down, and removing the crank handle.

The water service inlet pipe, if it meets the specs, must absolutely be connected to the grid, but it does not qualify by itself as THE earthing ground for the system.

[HeyBub]

My house, built in the '60s, has galvanized iron pipe throughout. It's built on a slab with all pipes in the walls and the attic.

Eventually, the iron pipe exits the wall to connect to the city water system. As the pipe leaves the house, it encounters a valve, then, on the other side of the valve, plastic to the city.

There is no connection between any of my water pipes and the earth -- unless you count the conductivity of the water itself.

[westom]

He was exposed as a repeated liar. So Bud must misrepresent what I said so as to insult. Bud is a sales promoter of scam products. He will not even admit to promoting his company products. He lies about what I posted because I identified him as unethical.

So many including Saltydog and HeyBub are now repeating what I accurately posted so many years ago. And was attacked by Bud because that is what a sales promoter does. Only earthing electrode that is insufficient is the cold water pipe. I said it then and was attacked by Bud for accurately citing code. All other electrodes are sufficient to meet code. I said it then and I repeat it again - into Bud's lying face. The only electrode that must always be supplemented by any other electrode is a cold water pipe.

Cold water pipe (with some rare exceptions) is insufficient as an earth ground according to paragraph 250.53(D)(2). Bud denied what that paragraph said in 2002 - and still denies it today.

Brian and Joseph McPartland in their book "National Electrical Code Handbook" (at least 25 editions) are even blunter in contradicting the electrically naive Bud:

and is the only one that may never be

a least one "additional" grounding

s the sole grounding electrode, by

Saltydog and so many other posters are correct. Up until 1978, a water pipe was the best earthing electrode. Then code changed. Cold water pipe electrode is now the least acceptable earth ground. Code changed decades ago. It required nasty Bud to read paragraph 250.53(D) (2) rather than attack others to promote his scam products..

Whereas a cold water pipe meets the definition of an earthing electrode, it is the only electrode so insufficient as to require any other earthing electrode. After 25 years, Bud still cannot learn that a cold water pipe is insufficient earthing. That would requirement him to learn facts rather than post insults.

In most cases, if the water pipe ground is the only earth ground, then earthing is insufficient for surge protection. Critical to protection is a short connection to earth - ie 'less than 10 feet' with no sharp wire bends and other requirements. Even pipe solder joints can compromise that earth ground. Pipe grounds are insufficient when too far away. Just another reason why most pre-1990 buildings need earthing upgrades. Do not have sufficient earthing also for surge protection. Ground alone does not avert more =91dead canaries=92. But a short connection to single point ground is essential =96 one requirement - to appliance protection. Which again contradicts nasty Bud's lies and says why his products will not avert the OP's damage..

[bud--]

I have consistently limited comments to "metal, 10ft..." which obviously does not apply to your house.

On the other hand what you wrote: "the purpose of attaching the electrical ground to a water pipe is not to ground the electrical system, it's to ground the plumbing system" is not true in general. And you reinforced Salty, who appears to not want metal water service pipes to be used for system earthing.

Limiting your post to plastic water service pipe would have solved the problem.

[salty]

What? You HAVE become westom.

[bud--]

It is the sole earthing electrode in my code compliant house.

I said in both posts that a "supplemental" electrode is required for all new services since the 1978 NEC (and some before then).

The good reason is, repeating from the NEC Handbook, "The requirement to supplement the metal water pipe is based on the practice of using plastic pipe for replacement when the original metal water pipe fails. This leaves the system without a grounding electrode unless a supplementary electrode is provided." A water pipe electrode is far better than the ground rods that were used as "supplementary" electrodes. Ground rods are there in case the metal water pipe disappears. (Fortunately ground rods are not likely to be used in new construction.)

You said that the water pipe was not to be used as an earthing electrode. "Although you always want the cold water line BONDED to the grounding system, it should never be THE ground. In fact, it does not meet code for that use."

In fact a water service pipe (metal, 10 ft...) has been required for a very long time to be an earthing electrode. It is clear from the NEC quotes provided. And I have always said *an* electrode, not *the* electrode. It is connected as an earthing electrode with a "grounding electrode conductor" using specific rules.

If the water pipe is not metal, 10 ft... it is not required to be used as an earthing electrode and then is "bonded for safety" under specific bonding rules.

[salty]

Go stand in the pedantic corner with w_tom