tt system

scott 123 · Apr 15, 2013

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

SPARTYKUS · Apr 15, 2013

Chemical bonding. Not glueing. Sounds much better

telectrix · Apr 15, 2013

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

all depends on your outlook mon together. side by side or screwed. like the old lady who had 2 cats that died. with being so attached to them, she decided to have them stuffed. so she went to the taxidermist to instruct him. he asked her if she would like them mounted. " no thanks" she replied. " just put them side by side"

power ranger · Apr 16, 2013

The last TT install like this i did the rod was totally corroded and pulled easily out of the ground. However the Zs readings were all quite low (about 40 ohms ). It wasnt until I checked the Ze that the problem became apparent and it was parallel paths through main bonds that brought the original Zs down.

So as a thought, Scott have you also checked and confirmed theintegrity of the bonding in this property as well?

GLENNSPARK · Apr 17, 2013

power ranger said:
The last TT install like this i did the rod was totally corroded and pulled easily out of the ground. However the Zs readings were all quite low (about 40 ohms ). It wasnt until I checked the Ze that the problem became apparent and it was parallel paths through main bonds that brought the original Zs down.

So as a thought, Scott have you also checked and confirmed theintegrity of the bonding in this property as well?

you cant rely on extranious for Ze...
you need to get a stable Ra....and the only way your goin to do that is with several 5/8" rods connected together and properly sited...about a meter away from any building edges and foundation rubble.....
depth is key with TT

power ranger · Apr 17, 2013

Glennspark, dont know if you misunderstood my post as I never said you could or should rely on extraneous metal to act as earth return. If i did that then why would I have bothered to checked the rod as the Zs were low anyway.

Without knowing the install i was just asking the OP if he had checked main bonds as he doesnt seem to have any parallel paths bringing down his Zs on his newly installed rfc.