no earth

[GLENNSPARK]

Absolute, how many times have you had an Ra reading of 150 or more and then carried out the same test on the incoming water main and found a reading of 20 etc, Im not saying you can use a water main as a stable earth you cant(plastic pipes etc) but if its sound and reliable then bobs your teapot.

place i was at a bit back....
recent panel...new colours so since 2005...but whoever had done it decided to use the lead water incoming as the means of earthing...
Ze=0.37
it wasn`t a case of leave as is indefinately....i explained to the client that the earthing arrangements needed upgrading...and arranged a PME connection for them at their request...
at least at 0.37 i was happy to leave as is until the DNO had been out....

 

[chilliwilly]

an instructor who i did the 2391 with told me about the time he used to work at sharlston pit..
he said they had been trying for years to get a stable earth....
there was an old tractor engine block in a field out the back of the pit....they found that no matter what the weather was like the Ra was stable on this....so thats what they ended up using as the main earthing `spike`....
he said they used it right until the pit closed.....

I thought they used an IT system in the mines, hardly an earth at all?

 

[GLENNSPARK]

I thought they used an IT system in the mines, hardly an earth at all?

well..i`m just going by what this chap was telling me...

- - - Updated - - -

would depend on the levels of fault current available...

 

[Mork]

Ofcourse, as a temp measure a water main is much more reliable than dodgy reading Ra on an electrode, however it could be replaced with plastic, so any pemenent matalic stucture that is soundly connected to earth and in your opinion doesnt deteriorate is acceptable as a reliable earth in aTT system.

 

[GLENNSPARK]

Ofcourse, as a temp measure a water main is much more reliable than dodgy reading Ra on an electrode, however it could be replaced with plastic, so any pemenent matalic stucture that is soundly connected to earth and in your opinion doesnt deteriorate is acceptable as a reliable earth in aTT system.

indeed but given that the DNO were going to be out in about 2 weeks from the time i called the duty engineer i was happy to leave as is...
we were on site every day so if there had been any diggery pokery going on with the water supplies out on the street we would`v known about it...and would`v acted accordingly (temp rod/s)

 

[chilliwilly]

The only thing is though if you can't get back for some reason, you have left a code 2 departure and your arse wouldn't touch in the (unlikely) event of a loss. Just make sure your scheme provider doesn't get a complaint about it or see it.

 

[GLENNSPARK]

The only thing is though if you can't get back for some reason, you have left a code 2 departure and your arse wouldn't touch in the (unlikely) event of a loss. Just make sure your scheme provider doesn't get a complaint about it or see it.

no...its been done (PMEd)...like i says at #65
and i`m not in the habit of leaving 2s either...lol....

 

[Geordie Spark]

no...its been done (PMEd)...like i says at #65
and i`m not in the habit of leaving 2s either...lol....

Good lad! :icon4: .:yesnod:

 

[GLENNSPARK]

Good lad! :icon4: .:yesnod:

yes i am arn`t i

 

[Geordie Spark]

yes i am arn`t i

Aye ye are ................... for a Tyke

 

[Engineer54]

Just a note for engineer 54, it doesnt half to be an earth rod to make it TT,any permenently fixed earth source will suffice.

So long as it meets the requirements of an electrical permanent electrode you'd be right. Such a suitable electrode would be for instance a Ufer earth, or say a steel building where the steel posts have been driven or concreted into the ground.

What isn't acceptable, is the use of extraneous service pipes that can be replaced by plastic service pipe at any time. It is also not generally permissable to use metallic service pipes, as the sole means of earthing to an electrical installation. So even in this case, it cannot be deemed a TT system!!

 

[GLENNSPARK]

Aye ye are ................... for a Tyke

i mean it would of course depend on the individual scenareo...
now, if we hadn`t been on that site every day for the time it took for the DNO to sort out a PME...i would of course not left it like it was..
but the first thing i did before anything else was get a Ze ..just to confirm there was actually an earth at the property (church)...and as i found it to be suitably low...i made the concious decision to leave it as is until the PME was done...
now if it was a case of just being there for ...say a couple of days..well, theres a different matter completely and a temporary rod would have been installed

 

[Geordie Spark]

i mean it would of course depend on the individual scenareo...
now, if we hadn`t been on that site every day for the time it took for the DNO to sort out a PME...i would of course not left it like it was..
but the first thing i did before anything else was get a Ze ..just to confirm there was actually an earth at the property (church)...and as i found it to be suitably low...i made the concious decision to leave it as is until the PME was done...
now if it was a case of just being there for ...say a couple of days..well, theres a different matter completely and a temporary rod would have been installed

Yes, of course Glen .... we believe you !! :wink_smile:

 

[Stroppy]

When I tested my home installation a few weeks ago out of curiousity I found the Ra to be fairly pants (by which I mean 'not good', not a pair of pants buried and connected to the earthing conductor, like GlennSparks tractor engine) around 120 ohms, but with all the bonding (gas and water) and the bent copper pipe with an earth connected to it, I got 0.something ohms instead. I know technically I should try to get the twig itself a bit better, but with a reading like that I'm not sure I'll bother! One day I will test the bent copper pipe that is hammered into the ground under the house on its own and see what reading that gives.

 

[telectrix]

wouldn't we all like to hammer a bent copper?

 

[Stroppy]

If he gives me a good earth I'll have a go!

 

[Engineer54]

Your down to less than an ohm on your bonded pipe work?? lol!! Sorry i find that extremely hard to believe, in fact i'll go as far as saying, i don't believe it!!!!!!! So why is your earth rod only giving you an Ra of 120 ohms??

 

[trev]

i`m not in the habit of leaving 2s either...lol....

We all get caught short at some point though.

 

[GLENNSPARK]

We all get caught short at some point though.

oops...sorry Trev your right...
i did a floater

View attachment untitled.bmp

 

[trev]

AAAAAAA Glenn you horrible dirty ****er