WARNING! WARNING! WARNING! (was [Elecraft] ESD recommendation)

[Ron D'Eau Claire]

Very true David. "Earthing" to the mains ground is the proper way to do it.
If there's a separate ground rod for any reason, such as an RF ground, most
codes require that it be connected to the mains earth ground as well.

It's worth making sure the mains ground is connected too! I've encountered
an astonishing number of missing ground connections, both in older homes and
in new construction! Here in the US at least, one can buy a simple tester
that plugs into the outlet being checked. Three lights indicate whether the
outlet is properly wired and, if not, what's wrong. For the very small price
they require, they're an excellent investment for anyone. 

Ron AC7AC

-Original Message-----

Modern electrical installations, at least in the UK, and I think also in 
the US, often use a system called Protective Multiple Earthing.  With 
this all exposed metal work in a building should be connected together 
and to the mains ground wire, but will not be connected to the actual 
earth at the property boundary (it will be connected to mains neutral). 
  If you have this sort of installation, you must not connect anything 
to true earth unless you are prepared to assume that you are connecting 
it to mains live, as, in some fault conditions, the difference between 
the true earth and mains earth voltage can be the full supply voltage.

(Such installations also require special consideration with respect to 
antennas and functional (RF) earths.)


-- 
David Woolley