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Topic Title: Earth rod location ????
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Created On: 05 August 2012 09:26 PM
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 05 August 2012 09:26 PM
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goldenboy1818

Posts: 503
Joined: 22 February 2011

What regs are there if you can not locate the earth rod of a tt installation ?? It is visible at the met block but can not find where it is staked , any advice would be greatly appreciated
 05 August 2012 09:39 PM
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hifly

Posts: 726
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if i could not find it i would put a new one in,

if you can't find it it may not be there, the wire might be on a water pipe somewhere.

-------------------------
Vince

Prove Dead Stay Alive


 05 August 2012 09:45 PM
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daveparry1

Posts: 6374
Joined: 04 July 2007

Best to put another one in even if the reading is good, as Vince said the cable might be on a water pipe, that was very common a few years ago,

Dave.
 06 August 2012 09:43 AM
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timothyboler

Posts: 230
Joined: 25 July 2008

Strictly speaking there is no regulation that stipulates that a means of earthing (and it's connection to the earthing conductor) needs to be readily accessible. Earth rods are often buried underground and exo-welded to the earth cables or even could be a rebar cage in a pile foundation or other structural steelwork.

Having said that if you can't trace an earthing conductor into the ground I'd agree with the above.

Regards, Tim

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Everyone loves a fireman - but hates the fire inspector.
 06 August 2012 03:44 PM
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GB

Posts: 368
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How can you verify the connections? 134.1.4 / 526.3
542.2 Earth electriodes how can you confirm everything complies particularily 542.2.6

 06 August 2012 06:21 PM
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timothyboler

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Hi GB. I was assuming that the OP was referring to a periodic inspection rather than an initial verification. In any case you would check buried connections "during erection" i.e. before you backfill; the regs take a pragmatic approach and 134.1 allows for this. 526.3 (i) excludes joints designed to be buried i.e. you would design for exothermically welded connections rather than mechanical compression clamps etc. to give enough confidence that the joints will be sound over the lifetime of the installation. Although you should always try and make the rod accessible if possible there will always be means of disconnecting the earthing conductor via tool at the MET for periodic resistance tests in isolation to any bonding per 542.4.2.

Regards, Tim

-------------------------
Everyone loves a fireman - but hates the fire inspector.

Edited: 06 August 2012 at 06:40 PM by timothyboler
 06 August 2012 08:44 PM
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GB

Posts: 368
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Hi Tim
I was replying to the op and just throwing in some regs that he could use to show / highlight that a new earth stake was required, as I thought he was looking for some regs to back up his findings.
anyway I was just killing some time watching another dramatic storm (rath of god, thunder and lightning etc) out the window and thought I would throw my two peneth in!!

Always a good forum tho for the responses and thoughts of those responding.

 08 August 2012 08:10 PM
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aligarjon

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what is the size of the cable. it used to be the that if it was 16mm or over the connection could be buried. not sure if its still the case though.or was that to do with mechanical protection ?

Gary

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Specialised Subject. The Bleedin Obvious. John Cleese
 09 August 2012 08:44 PM
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aligarjon

Posts: 2916
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Table 54.1

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Specialised Subject. The Bleedin Obvious. John Cleese
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