How many ground rods?

electrofelon said:
Who exact is "the client"? Usually it's an engineer or designer that is wasting the clients money and the owner should fire him. If it is truly the owner making the decision then all you can go is tell him he's wasting is money but you are happy to do what he wants as long as you get paid.
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I agree. The client doesn't know any better that's why they hired professionals to do the design in the first place. We did a huge apartment building with probably 2000 linear feet of footings with CEE's. They also had us install at least ten of the 3/4"X10' triangle rod nonsense with grounding test wells in the basement. Talk about a waste of money.
 
electrofelon said:
Who exact is "the client"? Usually it's an engineer or designer that is wasting the clients money and the owner should fire him. If it is truly the owner making the decision then all you can go is tell him he's wasting is money but you are happy to do what he wants as long as you get paid.
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The problem is that as an electrical contractor you end up paying for a clause in the contract that says that you as a contractor must follow the code, and the local regulations, blah, blah. But we did not find any article in the code that requires us to install a ground system like that.
The client is a school, the engineer who knows. As they are good clients, we accept the option they request, in the end it is not that expensive.
 
hillbilly1 said:
The field lights are nice lightning rods, so I can see that, the classrooms though have a much lower chance of lightning.
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It sounds logical, but there is nothing in the design that tells you about interconnection with the lightning protection system, and each light pole and score board has its own protection using an individual ground rod.
 
Charlypt said:
The problem is that as an electrical contractor you end up paying for a clause in the contract that says that you as a contractor must follow the code, and the local regulations, blah, blah. But we did not find any article in the code that requires us to install a ground system like that.
The client is a school, the engineer who knows. As they are good clients, we accept the option they request, in the end it is not that expensive.
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Yeah if it's in the contract and plans then you have to install it, I'm not saying you can skip it because it's not actually a code. Fortunately I am design build so I rarely have to deal with this crap. I'm probably too honest, but I treat my clients money like it was mine.
 
If he drew it that way and its not going to CAUSE a hazard just do it. You getting paid for it and its more work. What's to complain about? Its between the customer and the engineer.
 
Charlypt said:
It sounds logical, but there is nothing in the design that tells you about interconnection with the lightning protection system, and each light pole and score board has its own protection using an individual ground rod.
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But if anything gets past that protection it would help reduce the damage as designed at the service. The classrooms would more than likely have the surges come from the utility than the buildings.
 
Charlypt said:
Those engineers always try to kill us.
They have asked us for 3 - 20 foot rods in a triangle 10 feet apart where there is no space.
We had to join them with a coupling and install them at an angle due to the hardness of the terrain.


Thanks for making my point.
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I recall a couple of similar type things. 1 job required 3 3/4 grounds, fortunately not 20 feet. Had to drill rock to get them started. Nothing but a mess. Another job, a cell tower, we had to keep digging up the ground wire and cadwelding the new grounds to it. We could see various nicks in the wire where it had been hit by shovels before. But there were above ground plates fed by the same wire that we could have used. But they didn't like them for some reason.
 
hillbilly1 said:
The field lights are nice lightning rods, so I can see that, the classrooms though have a much lower chance of lightning.
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I don't know about the OP's situation but the ball field lighting I have done had anywhere from 12' to 30' deep 24" to 36" diameter pole bases loaded with rebar, it's doubtful a few rods would make any difference.
 
roger said:
I don't know about the OP's situation but the ball field lighting I have done had anywhere from 12' to 30' deep 24" to 36" diameter pole bases loaded with rebar, it's doubtful a few rods would make any difference.
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Please stop the critical thinking when it comes to ground rods. Ground rods are the only thing that work for grounding. Once I worked on multi-megawatt ground Mount PV system. Had a fence around the perimeter constructed with driven pipe. The spec showed a ground rod every hundred feet to ground the fence. 🙄
 
electrofelon said:
Please stop the critical thinking when it comes to ground rods. Ground rods are the only thing that work for grounding. Once I worked on multi-megawatt ground Mount PV system. Had a fence around the perimeter constructed with driven pipe. The spec showed a ground rod every hundred feet to ground the fence. 🙄
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But Chat GPT said ground rods would stop the lightning
 
You can’t say ground rods are absolutely worthless, I’ve had several jobs where they had lightning issues, and adding ground rods and proper bonding solved the problem. I have a neighbor that lives on top of a hill that all pasture, no trees. His fence charger got knocked out every time a storm came up. Installed two rods at the barn, two at the house, and two at the utility pole feeding the house. He hasn’t replaced a charger since. Another customer had a house below a rock quarry, lightning constantly taking out his tv and telephones. The phones and cable drops were at the opposite end of the house from the service, and were not bonded to the service. Added a rod at both ends, and buried a #4 bare copper between them. He hasn’t had a problem since.
Another customer was at the end of the poco line, and was constantly getting surges during storms. Added three rods, and problem stopped.
 
hillbilly1 said:
You can’t say ground rods are absolutely worthless, I’ve had several jobs where they had lightning issues, and adding ground rods and proper bonding solved the problem. I have a neighbor that lives on top of a hill that all pasture, no trees. His fence charger got knocked out every time a storm came up. Installed two rods at the barn, two at the house, and two at the utility pole feeding the house. He hasn’t replaced a charger since. Another customer had a house below a rock quarry, lightning constantly taking out his tv and telephones. The phones and cable drops were at the opposite end of the house from the service, and were not bonded to the service. Added a rod at both ends, and buried a #4 bare copper between them. He hasn’t had a problem since.
Another customer was at the end of the poco line, and was constantly getting surges during storms. Added three rods, and problem stopped.
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I doubt the rods did Anything. It's just chance. I
 
hillbilly1 said:
Another customer was at the end of the poco line, and was constantly getting surges during storms. Added three rods, and problem stopped.
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Can you explain, using electrical theory, how that would work? To have an in depth discussion about it, we would need to know whether the utility system is an MGN and also which conductor has elevated voltage. But let me run thru some possibilities : If the elevated voltage is on the (or 'one of the' in the case of it being Delta distribution) ungrounded conductors, I can't see any possible way more ground rods would do anything. If it's an MGN, maybe you have an elevated voltage on the neutral. Ok, that is a possibility, but I find it extremely unlikely adding a few more rods to an already well grounded neutral of an MGN would make any difference of limiting that elevated voltage, unless there was a problem with the MGN. If
 
electrofelon said:
Can you explain, using electrical theory, how that would work? To have an in depth discussion about it, we would need to know whether the utility system is an MGN and also which conductor has elevated voltage. But let me run thru some possibilities : If the elevated voltage is on the (or 'one of the' in the case of it being Delta distribution) ungrounded conductors, I can't see any possible way more ground rods would do anything. If it's an MGN, maybe you have an elevated voltage on the neutral. Ok, that is a possibility, but I find it extremely unlikely adding a few more rods to an already well grounded neutral of an MGN would make any difference of limiting that elevated voltage, unless there was a problem with the MGN. If
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Here there are a lot of end of line systems. Lightning travels to the end of line even with the poco grounding. Ours is wye, not delta’s.
 
hillbilly1 said:
Here there are a lot of end of line systems.
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. What does that mean?

Lightning travels to the end of line even with the poco grounding. Ours is wye, not delta’s.
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So with all the grounding on the line, probably hundreds of ground rods (depending on how big an area we want to bring into it of course). You think a couple more is going to make any difference? Also if the lighting hits the ungrounded conductor, which is usually on top and more likely I would think, more grounding of the neutral isn't going to change anything.
 
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