Auerswald SG-100 Manual De Instrucciones página 18

Earthing: when used as fine protection, the earthing must be
connected to the earthing on the telecomms device, as directly as
possible. You should not run the earthing circuits on the telecomms
device (usually via the protective earth conductor) and the module
separately. For this reason, it is a good idea, for example, to connect
the module's earthing with the protective earth conductor in the
mains socket for the telecomms device. A line with diameter 1.5
2
mm (Cu) is sufficient for earthing. A simple connection to the
protective earth conductor is all that is required to protect a
telecomms device that does not have its own earthing (e.g. a DSL
router, door terminal or remote telephone).
Important: Do not install the line to the telecomms device close to
a ground cable or the cables to the TAE socket/DSL splitter.
Important: After installation, restart the router.