On Wed, 29 Dec 2010 13:15:27 -0000, ARWadsworth wrote:

That should be TN-C-S, where an earth is not supplied by the
electric
company, the earth is connected to the neutral (dont do this
yourself).

The company does supply the earth for both TN-C-S and TN-S.

But not necessarily as a separate incoming conductor. The consumer PE
can be connected to the incoming neutral at the consumer end.

--
Cheers
Dave.