10 Sep
2014
10 Sep
'14
9:03 a.m.
On 09/10/2014 01:01 AM, Tothwolf wrote:
Likely due to diminishing return. Adding yet another
electrode isn't
going to help very much. In specialty applications where a low
resistance ground is required (radio communications for example), they
make special chemical type ground rods. It is also common to install
large ground rings in these sorts of applications.
Okay, so it's 25 ohms or less, so my memory isn't too bad. ;)
I recall this because the subject of well casings (normally galvanized
iron pipe) came up at one point in my life. I'd asked the local
inspector if it was permissible to use a deep well casing as earth
ground instead of the usual grounding rod if the well resistance to
earth ground was lower. His response was "no--it is the wrong material"
--Chuck