The problem with “wanting it safe” is that it is subjective. There is never total safety. One of the roles of building regulations is that the question is resolved in a way that can be understood by all.
A basic principal of our legal system is that you cannot be compelled to comply with laws that you have no way of knowing. The problem is that the builder has no way to know of requirements that were not adopted that only exist in the mind of the building official. A building official that does not understand this is a loose cannon. You would be incensed if a police officer imposed his own personal laws on you so why not when the building official does the same thing.
Regarding grounding, the goal is to have a ground resistance less than 5 Ohms (I have also heard 25 Ohms). Is this number or another number clearly stated in the electrical code and if so what is it.
Because of the hassle of actually measuring the ground resistance minimum requirements or rules of thumb have been adopted. But if you have a system with low enough resistance all the rules of thumb are irrelevant. Failure to comply with the minimum spacing between ground rods just means that the grounding will be less effective. If this is a problem do not abandon the offending ground rod just add another ground rod at least the minimum distance from the first ground rod. When you do this the system will be better.
It is my understanding the reason for introducing non conducting pipe in the water system is that this prevents grounding current from flowing in the water pipes and thus reduces the corrosion in the water distribution system.
A ufer ground is not effective if a membrane is placed under all of the footings as is the case in some areas/sites. When this is the case you have a floating ground.
"The problem with “wanting it safe” is that it is subjective."
Code is clear, easy to understand with subjectivity removed.
"There is never total safety."
But there is. In collaboration with Southern California Edison I have rendered many electrical installations totally safe.
"One of the roles of building regulations is that the question is resolved in a way that can be understood by all."
Following code and understanding code are sometimes divergent concepts harbored within a particular mass of brain matter. A great many practitioners of construction trades follow codes with no inkling of why.
"A basic principal of our legal system is that you cannot be compelled to comply with laws that you have no way of knowing."
Wrong as wrong can be. Break some arcane law and observe the result with your nose in a corner. "But teacher, I didn't know"
"The problem is that the builder has no way to know of requirements that were not adopted that only exist in the mind of the building official."
Well then, that's usually only a problem once. But yes, there are some dimwitted......well Shirley you get where I'm going with this.
"A building official that does not understand this is a loose cannon."
A loose cannon is a deadly hazard.....slamming around on the deck of a warship smashing conscripts to bits. The building official you are referencing is more of a sniper in a crows nest. He sees the cannon and it's random destruction while delivering pinpoint correction.
"You would be incensed if a police officer imposed his own personal laws on you so why not when the building official does the same thing."
With most folks, that is absolutely correct. Incensed? Such a mild term applies to a few. Pissed off applies to the many. But as Tommy, the oldest Henderson boy said, "Here's the thing about that" The correction could have come from a code book or perhaps my ass. Seldom does anyone know the difference.
"Regarding grounding, the goal is to have a ground resistance less than 5 Ohms (I have also heard 25 Ohms)."
Logically the usual goal is zero.
"Is this number or another number clearly stated in the electrical code and if so what is it."
25 to 6,100,000,000 can be found in the NEC. Clearly stated? That depends on the level of electrical engineering acumen one has achieved. PHD maybe.
"Because of the hassle of actually measuring the ground resistance minimum requirements or rules of thumb have been adopted."
Rules of thumb vary region to region. Here and there it's a thumb on the scale.....with others it's a thumb and a nose.....and yet others have a thumb up their ass. In my experience it is a thumb and a forefinger parroting code for all comers.
"But if you have a system with low enough resistance all the rules of thumb are irrelevant."
I do believe that you don't understand the rules that govern the rule of thumb. The relevance of the rule of thumb forces the outcome.
"Failure to comply with the minimum spacing between ground rods just means that the grounding will be less effective."
Duh! It's a "just" as in trifling??? This is the subjectivity that was left out of the code.
"If this is a problem do not abandon the offending ground rod just add another ground rod at least the minimum distance from the first ground rod."
"If"? Ther's no ifing in baseball. Toss in a rod you say....six feet from the first rod says you. It sounds like advice but is hardly sound advice.
"When you do this the system will be better."
Better than what exactly? Is better the best that can be accomplished? Follow the code rather than half baked internet musings and best is your companion.
"It is my understanding the reason for introducing non conducting pipe in the water system is that this prevents grounding current from flowing in the water pipes and thus reduces the corrosion in the water distribution system."
Could it be that plastic pipe is so much cheaper and easier to work with.
"A ufer ground is not effective if a membrane is placed under all of the footings as is the case in some areas/sites. When this is the case you have a floating ground."
That single sentence lends credence to the rest of what you have written. Shouldn't be that way...do I have permission to remove it?
