While the interconnection by wire tie is permitted (where
length of overlaps must be at least 20 times the diameter),
evidence shows that this is not suitable for a lightning-carrying
connection, i.e. high current-carrying connections. The upper
connection of the external LPS to the internal rebar carries the
highest current density. It is important that this connection be
secure, thus wire tie is not sufficient. CADWELD or welded
connections are recommended. Where mechanical clamps are
used, they should be approved to EN 50164-1 and either two