TT...installing 5/8" rods

[GLENNSPARK]

well...here I am again...this time its installing a TT system utilising 2X 5/8" rods...with the connector..:


here is the necessary gear as laid out (the 20mm PVC conny isn`t in the pic)


these are the type of rods you need...no 3/8" twigs here (apart from in that bush behind maybe)


site is about 1 1/2 meters away from the house...thats the first one in..now to connect the second onto the first ....and carry on...


still some way to go...


get it brayed in....Robert my assistant uses the fork with a bit of tape to keep the rod steady


thats a length of 10mm CSA G/Y being pulled through a length of conny for main earthing (the conny was dropped into the ground)

Ze was OK at just over 15 ohms...had to change the 16th edition setup in the board...it was configured as a split load 10 & 2....dropped another RCD in it and did it 5 & 5
happy days...:biggrin:

 

[Engineer54]

Very nice, I don't have nerves of steel like you so I usually dig at least 500mm first with a spade, I've hit too many drains and water pipes in my time so I'm a bit skittish.

Just out of interest don't you get a 2.4 meter rod which would save the need for a coupler? Also did you get 15ohms just testing the rod or was that after it was connected and possibly with parallel paths? If it was just the rod then that's very good ground, we usually need multiple rods or around 10-15 meters depth where I am to get an impedance that low

I'm with you here Marvo, ....i've never actually ever used a 1.2m rod in my life!! lol!!

Well as you have stated many times here, your driving rods into a sand based soil, and by the sound of the depths you have to go, all the sulphates etc, must have been well and truly washed out of that sand too... lol!!

 

[GLENNSPARK]

Leave it for 12 month or more to go back and check, If that rod isn't down to around 10 ohms, something is very wrong.
Better still, if you can monitor it 2 or 3 times a year, for the next 3 years. You'll get to see what i've been talking about on here all this time!! lol!!

well i was talking to Tony earlier....and he mentioned just this eng.....
the lady who owns the house would be happy i`m sure for me to bob round and `monitor it` for her...
i`ll give it a few months to settle eng...as you have mentioned here (and before in other threads).....and i`ll post the prognosis...

 

[GLENNSPARK]

He'll be retired and off to his retirement gaff in the Bahamas before then !!

funnily enough whilst i was reconfigurating the board for conformance the owner and her daughter were on about holidays...like where they`d been n all that lot....

 

[richy3333]

I saw the word assistant and searched for the glamorous blonde in a short skirt and high heels. How disappointed was I!

 

[Deleted member 9648]

Sorry Guys I still just dont get the euphoria and arse licking over 15 ohms....a fault current of 15a?...What use is that?
there was a 'best Ra' thread recently,and values as low as typical TN readings were obtained,now I applaud that.But 15 ohms?....you are utterly deluded if you think 100-200 ohms is laughable and yet accept 15. Both readings are reliant on an RCD to meet disconnection times,and there will be no difference in disconnection times with either reading.
Before I get accused of being exclusively a twig merchant let me state now I use both twigs and coupled rods where appropriate. Two coupled rods on a small sewage plant at a pub recently got 12 ohms as a replacement for a bit of copper tube reading 700 ohms......only yesterday I installed a very temporary shed with just a light and socket,only warrented a twig and I got 20 ohms.....but unlike you lot I am not kidding myself that those readings are doing what a 100 ohm reading wont.....20 ohms with a twig? I'd have been just as happy with 120.
Perhaps Glenn...Tel...E54 etc can explain to me what 15 ohms will do that a reading 10 times that wont,and maybe I'll see the error of my ways. But I seem to recall asking this before and never getting a satisfactory answer so I wont hold my breath.

 

[GLENNSPARK]

Sorry Guys I still just dont get the euphoria and arse licking over 15 ohms....a fault current of 15a?...What use is that?
there was a 'best Ra' thread recently,and values as low as typical TN readings were obtained,now I applaud that.But 15 ohms?....you are utterly deluded if you think 100-200 ohms is laughable and yet accept 15. Both readings are reliant on an RCD to meet disconnection times,and there will be no difference in disconnection times with either reading.
Before I get accused of being exclusively a twig merchant let me state now I use both twigs and coupled rods where appropriate. Two coupled rods on a small sewage plant at a pub recently got 12 ohms as a replacement for a bit of copper tube reading 700 ohms......only yesterday I installed a very temporary shed with just a light and socket,only warrented a twig and I got 20 ohms.....but unlike you lot I am not kidding myself that those readings are doing what a 100 ohm reading wont.....20 ohms with a twig? I'd have been just as happy with 120.
Perhaps Glenn...Tel...E54 etc can explain to me what 15 ohms will do that a reading 10 times that wont,and maybe I'll see the error of my ways. But I seem to recall asking this before and never getting a satisfactory answer so I wont hold my breath.

look...i do understand what your saying...
i will be monitoring this...(as i have already said)...it should come down significantly...if not..then i can always send another rod in...cant I...
its not just about the levels its at now is it.....its about stability and the only real way of acheaving this it to go deep....that means 5/8" rods with connectors....and its this that me, eng, tel etc keep on about...:biggrin:

 

[Engineer54]

Sorry Guys I still just dont get the euphoria and arse licking over 15 ohms....a fault current of 15a?...What use is that?
there was a 'best Ra' thread recently,and values as low as typical TN readings were obtained,now I applaud that.But 15 ohms?....you are utterly deluded if you think 100-200 ohms is laughable and yet accept 15. Both readings are reliant on an RCD to meet disconnection times,and there will be no difference in disconnection times with either reading.
Before I get accused of being exclusively a twig merchant let me state now I use both twigs and coupled rods where appropriate. Two coupled rods on a small sewage plant at a pub recently got 12 ohms as a replacement for a bit of copper tube reading 700 ohms......only yesterday I installed a very temporary shed with just a light and socket,only warrented a twig and I got 20 ohms.....but unlike you lot I am not kidding myself that those readings are doing what a 100 ohm reading wont.....20 ohms with a twig? I'd have been just as happy with 120.
Perhaps Glenn...Tel...E54 etc can explain to me what 15 ohms will do that a reading 10 times that wont,and maybe I'll see the error of my ways. But I seem to recall asking this before and never getting a satisfactory answer so I wont hold my breath.

Here we go again the ''rather do nothing Guru'' has to have his say!! The difference between those that achieved very low values and yourself, is that they actually put the effort in, unlike yourself, that can't see the point, to putting any effort into a TT install. Which is fine, just don't encourage others to be the lazy sod that you are, when it comes to getting a TT system down to single figures or even to TN values, that you seem to advocate as being neigh impossible!!

 

[Engineer54]

look...i do understand what your saying...
i will be monitoring this...(as i have already said)...it should come down significantly...if not..then i can always send another rod in...cant I...
its not just about the levels its at now is it.....its about stability and the only real way of acheaving this it to go deep....that means 5/8" rods with connectors....and its this that me, eng, tel etc keep on about...:biggrin:

I'm afraid he doesn't care much about stability either, and has stated as much a few times in the past!!!
An RCD is his answer, cause it says so in the BGB!! lol!!

 

[Deleted member 9648]

Perhaps Glenn...Tel...E54 etc can explain to me what 15 ohms will do that a reading 10 times that wont,and maybe I'll see the error of my ways. But I seem to recall asking this before and never getting a satisfactory answer so I wont hold my breath.

Here we go again the ''rather do nothing Guru'' has to have his say!! The difference between those that achieved very low values and yourself, is that they actually put the effort in, unlike yourself, that can't see the point, to putting any effort into a TT install. Which is fine, just don't encourage others to be the lazy sod that you are, when it comes to getting a TT system down to single figures or even to TN values, that you seem to advocate as being neigh impossible!!

Thanks for that 'useful explanation' of your point of view. You really are an arrogant,snotty,bitchy see you next tuesday.......your policy if someone has the temerity to actually disagree with lord E54 is always to resort to insult. you constantly bang on about the follies of relying on RCD protection and then pat yourself on the back over an Ra value which relies on RCD protection!
Prat.

look...i do understand what your saying...
i will be monitoring this...(as i have already said)...it should come down significantly...if not..then i can always send another rod in...cant I...
its not just about the levels its at now is it.....its about stability and the only real way of acheaving this it to go deep....that means 5/8" rods with connectors....and its this that me, eng, tel etc keep on about...:biggrin:

Thankyou Glen for a proper explanation.Perhaps you can keep us updated on readings over time?

I'm afraid he doesn't care much about stability either, and has stated as much a few times in the past!!!
An RCD is his answer, cause it says so in the BGB!! lol!!

It's yours as well with many of the Ra values you quote on this forum to aim for(10 ohms Is the most common value you seem to come up with)...only you are too thick to see it.

 

[44ALLAN]

10 ohms is 23 Amps fault current whats wrong with that fgs?

It'll trip a 32 Amp Mcb in.................well..............hmmmmm............errrr.

Give me a few minutes while I google the 'get-out' clause in the regs mate

Also............
Keep ya heed bonny lad

 

[Silly Sausage]

Thanks for that 'useful explanation' of your point of view. You really are an arrogant,snotty,bitchy see you next tuesday.......your policy if someone has the temerity to actually disagree with lord E54 is always to resort to insult. you constantly bang on about the follies of relying on RCD protection and then pat yourself on the back over an Ra value which relies on RCD protection!
Prat.


Thankyou Glen for a proper explanation.Perhaps you can keep us updated on readings over time?


It's yours as well with many of the Ra values you quote on this forum to aim for(10 ohms Is the most common value you seem to come up with)...only you are too thick to see it.

In keeping with a classical engineering principle, KISS, I would replace the above post with...
---- Off Eng! :smilielol5:

 

[Dcf]

It's a basic sparkie work method passed from man to boy
get the ra as low as we can son.
saying that widdler is spot on with what he says too
can we call it a draw?

 

[Marvo]

Come on guys, please keep it civil !!!

 

[NDG Elecs]

As a relatively inexperienced spark what is the appeal of a 5/8 over the thinner rods?

I have only ever installed a handful of new rods and always use the 5/8 mainly because they are obviously stronger. The surface area is not that much greater so does not make much difference to Ra when compared to a thinner rod.

So it is just a strength thing i.e. they can take a better hammering to get them deep enough....

 

[Engineer54]

Thanks for that 'useful explanation' of your point of view. You really are an arrogant,snotty,bitchy see you next tuesday.......your policy if someone has the temerity to actually disagree with lord E54 is always to resort to insult. you constantly bang on about the follies of relying on RCD protection and then pat yourself on the back over an Ra value which relies on RCD protection!
Prat.

Oh dear, ....have i upset you??
Before you start slinging the innuendo's and mud in my direction, perhaps you ought to look back on your previous posts on this subject. By the way, ....I've stated nothing that you haven't quoted yourself!! I praise, as you put it, when someone makes a concerted effort in doing a job properly!! The Prats, are those like yourself that can't see the point, or just can't be arsed, (which is fine to a point), but then want to ridicule those that do!!

It's yours as well with many of the Ra values you quote on this forum to aim for(10 ohms Is the most common value you seem to come up with)...only you are too thick to see it

Your right, well to a point anyway, as i reckon that in most circumstances you should be able to obtain around a 10 ohm Ra value using two 5/8'' rods. Which i also consider and stated many times, as being the ''minimum'' rod size and length that should be used for providing any TT system, as it will also provide the integrity, of providing the system with the all important stability.

I have told you before, i'm many things to different people, but i can assure you, i am no-bodies bloody fool, least of all yours!! As far as i am aware from my employers, i'm also not paid to be thick!! lol!!