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Discussion Starter · #1 ·
It's been a while since I have done any grounding. What is the maximum resistance between the ground rod and earth?
 

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250.56 Resistance of Rod, Pipe, and Plate Electrodes
A single electrode consisting of a rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode of any of the types specified by 250.52(A)(2) through (A)(7). Where multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.
 

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One rod 25 ohms drive two rods and anything you get or don't get, because there is no requirement to measure the resistance.
 

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That is not how you measure ground resistance and most likely means little to nothing.

Second who is requiring this?

What if anything is the spec?
 

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Discussion Starter · #9 ·
I'm stuck in Iraq. I don't have the right equipment. I don't have a good ground and I am trying to get one. The sand here is unbelievable and goes down forever.
 

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WHY WHY WHY.......WHY..


What is the requirement requiring this GOOD GROUND WHY.

I am not being sarcastic I am SERIOUSLY trying to understand why. What is driving this?
 

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I'm frustrated. We've had at least 12 soldiers die of electrocution due to poor grounding. The pressure is on us to make sure we have it and rightfully so. We are having a hard time getting it and I am looking for some suggestions.
 

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In our industry there is this driving need to have a low resistance to earth. In the realm of all electrical requirements for safety this ranks at the bottom of the list.

Are there times where a low earth resistance is necessary YES, but seldom is this the case in a typical electrical installation, Good bonding YES, Low resistance grounding utilizing ECG's between equipment yes. But driving a rod into the earth. WHY?
 

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Driving a ground rod will NOT(!) cure an electrocution problem!

I can't believe there are no engineers (or whatever) there that know this.
 

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NO you did not, you has 12 electricians die from poor electrical wiring and poor BONDING of all metallic parts. Earth has nothing to do with this and until you (those involved in this not necessarily you) understand this some will continue to be hurt.

Hell if the earth is that lousy of a conductor, it is actually safer you can hold a ungrounded/hot/energized conductor and stand bare naked on the earth SAFELY.

SCREW THE GD EARTH... install proper wiring with proper grounding (BONDING) of all metallic parts.
 

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I'm frustrated. We've had at least 12 soldiers die of electrocution due to poor grounding. The pressure is on us to make sure we have it and rightfully so. We are having a hard time getting it and I am looking for some suggestions.
They did not die from poor grounding. They died from poor bonding.

What will a stick in the earth do to prevent these deaths?
 

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I'm stuck in Iraq. I don't have the right equipment. I don't have a good ground and I am trying to get one. The sand here is unbelievable and goes down forever.
What makes a good ground? if you dont have the right equipment, how do you know you have a bad ground? FWIW, it has nothing to do with clearing a fault and tripping the OCD...
 

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I have dug around rods & put a piece of terra cotta tile or pvc up on end fill it with rock salt and water it then take a reading drops the resistance real quick in normal soil,If you dont have any enviromentalist /tree huggers copper sulfate works good. dont know what chemical to use for sand?

They sell rods that are hollow you can put chemicals in .
 

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I have dug around rods & put a piece of terra cotta tile or pvc up on end fill it with rock salt and water it then take a reading drops the resistance real quick in normal soil,If you dont have any enviromentalist /tree huggers copper sulfate works good. dont know what chemical to use for sand?

Is lightning a huge threat in the desert?
 

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CMEC:

There are a variety of methods for lowering ground resistance, do a web search, DEEP EARTH GROUNDING, XIT, hell if I thought it would help I'd GIVE a 3-point tester, pay the shipping and give an online tutorial to billy716, BUT this is not the problem, not the issue, not the solution.

I want him and all our soldiers and contractors to be safe. There are ways to make this happen but peeing on a stick in the earth ain't he solution.
 

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I've read about this. Soldiers dying in the showers. I wondered at the time what was wrong, but it sounds as if it is more than just inadequate ground. I am guessing you use generator power over there. Whatever is causing this might be coming from energized piping and a good earth ground in the same area. Electric water heaters? Maybe you don't need water heaters in Iraq. If you have an overhead distribution system with a common grounding point that is tied to neut, then maybe that bond has failed. For all I know, you don't even use 2 hots and a neutral like we do in the states.
Measure across various pipes to drains or metal dividers until you find where the voltage is. Then shut down all power to your site and measure again. If the voltage is gone then turn on circuits one by one until it appears again. Then troubleshoot that circuit. If the voltage does not go away, then suspect your nearest neighbors. Check for solid neutral connections at neighbor's panels. You can even get voltage from phone wires that are damaged and lying on anything conductive. eg. metal pipes. roofing, metal walls. I don't know if phone voltage is enough to kill a person though.
This situation is tragic. You guys over there have enough to worry about without having to think about checking out in a shower where you should be safe.
Good luck and may God bless all of you.
 
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