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Anonymous Poster #1

Ground Rod Resistance Value

11/01/2011 2:47 AM

Dear friends, I have one problem concern the grounding. In my new boiler project we put one nine meter 20 mm stainless steel copper coated ground rod and then we measured the ground resistance of the rod In that time we are got 35 ohms. This is always not acceptable and I dont know that what the hell is going downside the soil. But we got the 5 ohms from the existing three meter ground rod in the same area. Now I have one strong doubt that is one medium voltage line is passing very near to the new ground rod,and this medium voltage makes some disturbance to our ground rod. Now I want to confirm wheather the inductance effect of the medium voltage line makes any disturbance to our new installed ground rod or not. This is only my doubt. Also I want to know that why the new installed ground rod always giving the high resistance value.
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Anonymous Poster #2
#1

Re: Ground rod resistance value

11/01/2011 6:29 AM

V=IR and Vab=Va-Vb
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ducon
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Join Date: Dec 2006
Location: Hop around Toronto, New York & Karachi
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#16
In reply to #1

Re: Ground rod resistance value

11/02/2011 1:41 PM

Dear friend , you saw what happened with Anonymous # 1. Please register because you do also post good answers. Lets not be CR4 members but family

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Munster
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Join Date: Nov 2011
Location: New Hampshire
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#2

Re: Ground Rod Resistance Value

11/01/2011 1:39 PM

How did you measure the resistance in reference to the ground rod? Also, did you use a 9 meter long rod, or three 3 meter rods?
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6
PeterT
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Join Date: May 2010
Location: Liverpool, NY
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#3

Re: Ground Rod Resistance Value

11/01/2011 2:56 PM

Why are you installing a new, separate ground rod for the new boiler equipment? Your equipment should all be connected to the same ground system. Do your local codes not permit you to bond to the existing, acceptable rod and its ground system?

The medium voltage cable in the vicinity of the rod may affect its resistance, but probably not to the extent that it tests 35 ohms. The more likely reason is poor soil conditions: too dry, too little salts/electrolytes, too much rock, etc. Have you done a soil boring in that area to know what the conditions are? Can you add grounding enhancement materials?

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wareagle
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Location: Alabama
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Good Answers: 63
#4

Re: Ground Rod Resistance Value

11/01/2011 4:34 PM

Good answer PT.

Did you remove the grounding conductor from the old rod when you measured the 5 ohms?
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WJMFIRE
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Join Date: Apr 2009
Location: USA, Florida
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#5

Re: Ground Rod Resistance Value

11/01/2011 11:08 PM

Use the existing ground rod or install a new solid copper (not coated) ground rod.

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leveles
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Join Date: Jan 2008
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#6

Re: Ground Rod Resistance Value

11/01/2011 11:29 PM

#2 that was downright naughty. You expect someone to measure voltage differences between grounds? That is surely beyond procedures.

A tied together ground mat, maybe. Measured as one.
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pnaban
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Join Date: Jun 2010
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#7

Re: Ground Rod Resistance Value

11/02/2011 2:12 AM

What is the material of construction of the existing 3m ground rod?.

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ducon
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#8

Re: Ground Rod Resistance Value

11/02/2011 2:41 AM

You again? You are out there only to get the idea to your problem and impress your boss for a better position and financial gain. You simple wait for all answers from CR4 members to pick out the reasons and 'WOOOSH" you vanish from the site without answering the questions of most CR4 members. this is why you have never registered!!!! You do not disclose who you are/ which country/city. you are a Pakistani from lahore with this Fludized bed boiler that was imported last year and you are passing through problems that you asked answers for in the "Mechanical" Section: PR not lifting, Bed coils damaged? etc/. etc.

Attention: All CR4 members, please check the Mechanical Section and it is simple a waste of time with him.

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fredart
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#9
In reply to #8

Re: Ground Rod Resistance Value

11/02/2011 5:07 AM

Good observation Ducon, I noticed the same. Ever since registering for this site became compulsory "Anonymous Poster #1" has been putting forward the most unlikely and stupid questions and hardly ever reacts to any replies. Maybe a separate section ("Posts by Anonymous Poster", subtitled "to be ignored") should be established, so as to get rid of this nuisance?

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ducon
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#10
In reply to #9

Re: Ground Rod Resistance Value

11/02/2011 8:23 AM

Thanks fredart. CR4 is really a fantastic engineering site and gaining popularity. CR4 should do something like any "anonymous poster" coming from same site more than once to be asked to registered so that other CR4 members are not just taken for a ride to help them in their better-position/financial gains. Thanks for the support and GA vote.

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Rockyscience
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#11
In reply to #10

Re: Ground Rod Resistance Value

11/02/2011 8:38 AM

I agree,98%.

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ducon
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Join Date: Dec 2006
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#14
In reply to #11

Re: Ground Rod Resistance Value

11/02/2011 1:38 PM

Thank you Rockyscience

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KJK/USA
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United States - Member - Member Engineering Fields - Electrical Engineering - Electrical Construction

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#13
In reply to #8

Re: Ground Rod Resistance Value

11/02/2011 11:27 AM

Nice catch ducon.

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ducon
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#15
In reply to #13

Re: Ground Rod Resistance Value

11/02/2011 1:39 PM

Thank you KJK/USA

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HiTekRedNek
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#12

Re: Ground Rod Resistance Value

11/02/2011 9:23 AM

You should be very qualified to answer that question, you have an insulated brain, and grounded Arse..

Sounds kinda like an "I dee ten tee" error to me.

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Users who posted comments:

Anonymous Poster (1); ducon (5); fredart (1); HiTekRedNek (1); KJK/USA (1); leveles (1); Munster (1); PeterT (1); pnaban (1); Rockyscience (1); wareagle (1); WJMFIRE (1)

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