Did I say that? I thought I said the electrode puts the neutral at the same potential as ground.
Grounding a Service
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Holt is long winded but man you forget how knowledgeable he is.
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I do not want to put words in your mouth BUT.......
IMO, the purpose of the grounding electrode conductor is simply to drain any voltage spikes to the earth rather than thru the house. Ground rods in most areas are not very useful but a concrete encased electrode can be beneficial to accomplish this goal.
Brian, I have had many electricians tell me that the grounding electrode conductor is there in case the neutral fails.... And these were licensed guys. Grounding is probably the hardest thing to understand in the nec
Brian, I have had many electricians tell me that the grounding electrode conductor is there in case the neutral fails.... And these were licensed guys. Grounding is probably the hardest thing to understand in the nec
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I am not talking safety, I am not talking NEC, I am asking how many electricians on this forum think an AC or DC distribution system will work without a metal rod stuck into the Earth.
I have had several discussions that turned into arguments with electricians that insisted you need a ground rod for an electrical distribution system to operate. I was amazed at their lack of knowledge and common sense. In the end, my last comments are how to airplane electrical systems operate and come to my office I'll do a setup and prove you wrong. They basically told be F' off or ignored me.
I would bet most electricians on a forum know better because they bother to belong to a forum to discuss the trade. But do a poll at work and ask fellow electricians.
Does a power system need to be grounded to Earth to work?
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Grounding is not necessary as there are ungrounded systems.
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..and a floating wye (no ground rod) would still work.
I think it is soooooooo important that the NEC requires a ground rod to be at less than 25 ohms resistance to ground and if it is not you need two rods. But don't bother testing the second rod as it doesn't matter, it will be fine, hahahahahah,
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Just drop two rods & be done with it.
Yes, Imo it would take forever to get under 25 ohms with rods however a concrete encased electrode can get there easily. I measured my concrete encased electrode years ago and got 13 ohms. I had 2 rods at the same site and I had 89 ohms.....
I don't understand why people fight the concrete encased electrode. In NC they amended it so you don't have to install a concrete encased electrode. We always did unless the builders forgot. We had to stay ontop of that.
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Depends on the type of system. If theres controls involved an ungrounded neutral could cause unpredictable actions in control circuits. In distribution systems it will not have an effectect in unbalanced systems it can cause overheating if the sum of the loads not equal 0
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Yep I agree, a concrete encased electrode is a much better option. If its new construction, its already available. Concrete works so well, you can merely splash water on a pool deck and check continuity back to the light junction box or anything else bonded to the pool shell with one lead on the wet concrete.
As to the original post a connection to earth is not necessary for a system to function properly under normal conditions. It helps with other issues that arise like static voltage discharge, etc. There was a post recently on here with examples of ungrounded transformer secondary's that were required by NEC to be un-grounded. All of those systems operate just fine without a connection to the earth. Bonding is far more important for safety, proper boding will clear a fault on branch circuits and feeders.
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I agree, I think they forget that voltage is between 2 points and if it's voltage to ground you have to have a ground reference. But with no reference to ground it operates just fine. A classic, simple example is the old school 2 prong razor receptacle.
I will add that many, far better electricians than me, make that mistake.
Well sure, in an intact service, excluding the supply, and an installation in good repair, it will work just fine without an electrode.
Have you ever clamped a GEC and found current flowing on it?
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As part of my job I do grounding investigations, so yesWell sure, in an intact service, excluding the supply, and an installation in good repair, it will work just fine without an electrode.
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Yep, we had a site that was impedance grounded and the UPS's worked but would not parallel.
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