Grounding Resistance 2

[gary071]

Hi, everyone.
It is measured that the earth resistance for a particular grounding is more than 20 ohm.In fact,the earth resistance is required to be less than 5 ohm.Instead of planting a new earth chamber into it, it is any other solution to lower down the earth resistance?Is it a practical way that bonding the copper tape all around with other grounding?But ll it give a steeve decreasing from 20 ohm until less than 5 ohm?

 

[Zogzog]

Larger diamater rods, longer rods, parrell rods will all help but probally not down to 5 ohms, there is a treatment for the surronding soil that you can try. try the AB chance website for some advice.

Scott Peterson
Training Manager
Power Plus Engineering

http://www.epowerplus.com

 

[rbulsara]

20ohms per rod is not uncommon. You need to use multiple rods at least 10 feet apart and bonded together to form a grid. This would be least expensive in my opinion and more effective.

There are other means too. Wihtout particulars of the site, its difficult to determine from here.

 

[cuky2000]

Zpgzog,

What is parrell rod? Do you mean “parallel rod”?

Beware that rod diameter has little effect improving the grounding resistance. The other methods mentioned are more effective for this purpose including Uffer ground, soil treatment, multiple rods, etc.

Here is some additional information that may be helpful.

http://cuky2000.250free.com/GND_Multiple_Electrodes.pdf

 

[arcflash99]

What are the soil conditions where the grounding rods are located?

Sandy? Rocky? Dry? It would seem like these conditions would require soil treatment.

I work in South Louisiana and the only times I have had high (but still less than 20 ohms) is when the contractors drive them in backfill soil from an excavation. The soil is nolonger compacted so the pressure from the soil gives a high resistance reading. Our solutions have been to use a coupling rod, or, drive another rod in compacted soil and bond to the grid.

Good Luck.

 

[Zogzog]

Culky,

Yes I meant parallel, sorry for the typo, I think everyone knows what I meant. Increased diamater will help, however not much, it was only one of several methods I mentioned (Inclluding soil treatment).

Why does it seem like you love slamming people, I was just trying to give the guy some ideas. I would have to assume you were talking to me, you said zpgzog, what is that? Did you mean zogzog?

 

[cuky2000]

Zogzog,

Sorry if I give you the impression that I am slamming you. As you, I would like to contribute with some ideas and at the same time learn new techniques.

 

[gary071]

arcflash99,
It's plant on a dry sandy place.i think the soil compact is not a problem.
Thanks anyway.

 

[Zogzog]

cuky,

Sorry, I quit smoking this week and am pretty defensive and a pian in everyones behind.

 

[Zogzog]

cuky,

Sorry, I quit smoking this week and am pretty defensive and a pain in everyones behind.