tt system

[scott 123]

just done a new ring main on a tt system ..ze at source is 355..(r1+r2)= 1.3 ..measured zs at socket 296 still more than 200ohms recommended whos responsible for getting it lower me or the provider

 

[telectrix]

you. well, at the customer's expense, of course. TT system earthing is the customer's responsibility. bang in a couple of 5/8" screwed together rods, at least 3 ft from the building.

 

[scott 123]

you. well, at the customer's expense, of course. TT system earthing is the customer's responsibility. bang in a couple of 5/8" screwed together rods, at least 3 ft from the building.

can I knock 1 next to the 1 that's already there and link the two with 16 mm

 

[telectrix]

rods should be spaced 1.5 x rod length. the existing rod is probably a 3ft. twig. depth is more important. i would start afresh with screwed rods. get at least 2m depth. and away from the builder's rubble that will be next to the wall.

try to miss incoming service cables/pipes/etc. LOL.

 

[tony mc]

Have you looked at the possibility of TNC-S with the DNO ?

 

[Engineer54]

rods should be spaced 1.5 x rod length. the existing rod is probably a 3ft. twig. depth is more important. i would start afresh with screwed rods. get at least 2m depth. and away from the builder's rubble that will be next to the wall.

try to miss incoming service cables/pipes/etc. LOL.

No1!! ....lol!!

As stated Depth is the key to roded TT installations, to ensure both it's stability and for enhanced Ra values... Also it's advisable to install a flush to ground concrete, or heavy duty plastic earth pit, (not one of those black PVC adaptable box things) for rod position identification and ongoing maintenance purposes...

 

[GLENNSPARK]

No1!! ....lol!!

As stated Depth is the key to roded TT installations, to ensure both it's stability and for enhanced Ra values... Also it's advisable to install a flush to ground concrete, or heavy duty plastic earth pit, (not one of those black PVC adaptable box things) for rod position identification and ongoing maintenance purposes...

absolutely....and often overlooked....
ir they go for the `budget` option...and get one of those box cap thingys...that just perches pathetically on top of the rod.....totally unsuitable wherever theres a risk of damage to the rod.....
at the end of the day..this is the main earthing arrangements...so i cant understand why so little consideration would be paid to it....

 

[scott 123]

absolutely....and often overlooked....
ir they go for the `budget` option...and get one of those box cap thingys...that just perches pathetically on top of the rod.....totally unsuitable wherever theres a risk of damage to the rod.....
at the end of the day..this is the main earthing arrangements...so i cant understand why so little consideration would be paid to it....

so obvious ..I've only just noticed incoming earth only 10mm will 16mm bring it down enough

 

[telectrix]

that. will make about as much difference as pi$$ing in the atlantic

 

[tony mc]

so obvious ..I've only just noticed incoming earth only 10mm will 16mm bring it down enough

No it will make no difference !

 

[GLENNSPARK]

so obvious ..I've only just noticed incoming earth only 10mm will 16mm bring it down enough

where have i mentioned here about increasing CSA of main earthing conductor in an attempt to get the Ra down?
you need to be looking at the rod.....and deciding what actions to take....
let me give you a pointer: rod..s!!

 

[trev]

See post 2 mate, if you don't know how to do this then don't be scared to ask.

 

[telectrix]

a 10ft length od scaffold tube would make a good rod. get wade88 to weld a lug on it. don't let him glue it, though.

 

[MDJ]

the 5/8 rods screw together and are 5ft long, 2 of them together should improve results.

 

[GLENNSPARK]

a 10ft length od scaffold tube would make a good rod. get wade88 to weld a lug on it. don't let him glue it, though.

no...that would consitute an earth `bonding agent`....think pat testers......