On Wed, 4 Jan 2017 16:02:42 -0500
burfordTjustice wrote:

On Wed, 04 Jan 2017 20:00:22 -0000
"James Wilkinson Sword" wrote:

On Wed, 04 Jan 2017 19:13:21 -0000, mike wrote:

On 1/4/2017 10:48 AM, burfordTjustice wrote:
On Wed, 04 Jan 2017 10:42:34 -0800
mike wrote:

On 1/4/2017 9:58 AM, James Wilkinson Sword wrote:
Somebody in one of these two groups recently said that a
concrete based house means you're earthed. Concrete is a
bloody good insulator!

Sorry, can't find the post it was mentioned in.

Can't help with a link, but I recently replaced my water main
with PEX. That broke the ground to the house and wouldn't pass
inspection. Long story short, research indicated that using
rebar in concrete was a trend in establishing a safety ground.
Apparently, there's enough conductive salt and water in concrete
to make it work, as long as the concrete sits on the ground and
you're not in the desert. Contact resistance is high, but
there's a lot of area.

I followed the code and installed two ground rods.
I did some impedance measurements between the rods and the
electrical system ground (before connecting) and determined that
the "grounding" was insufficient to do anything more than
dissipate static electricity, but the
inspector liked it.
I'd guess that hooking to the rebar is at least as good.


"James Wilkinson Sword" is in the UK...different rules
Question wasn't about rules.
Was about concrete as a ground. Unlikely it's much different in
the UK.

It was more about getting an electric shock by standing on the floor
of your house while touching something live. This was suggested by
someone recently as being a danger. I just measured some concrete
to make sure I wasn't being ignorant, and it was off the scale
(20MOhms)


LOL Please post a picture of you taking the measurement.

Well?