Would an LAN output connector of a laptop computer intended for connection to a router within the same building, be defined as a paired conductor external circuit as per ID 1 of table 14 within EN 62368-1.
Local Area Networks (LAN) (or Ethernet) connectors employing twisted pair conductors are considered paired conductors. See sub-note a) of Table 14.
However, also note that the first informative note at the bottom of Table 14 also states,” In general, for EXTERNAL CIRCUITS installed wholly within the same building structure, transients are not taken into account. However, a conductor is considered to leave the building if it terminates on equipment earthed to a different earthing network. “
Per associated industry specifications, such as IEEE 802.3, some LANs may be routed outside buildings. In fact, the existing IEC TR 62101, Electrical safety - Classification of interfaces for equipment to be connected to information and communications technology networks, views some LAN as Network Environment 0 (transients not considered) and some as Network Environment 1 (transients considered). Currently, IEC TC108 is updating IEC TR 62102 to refresh its information and make it more aligned with the current IEC 62368-1.
In the meantime, if it is the intent of the AV/ICT equipment manufacturer via an instructional safeguard that the LAN connection is intended to be connected to a network not leaving the building, per the informative note mentioned above associated with Table 14, there is not a need to consider transient voltages associated with such a LAN connection. This view may need to be revisited when IEC TR 62101 is updated and correlated with IEC 62368-1.