A31003-H8100-J100-01-7631, 09/2021
OpenScape Branch 550 / 550 HA, Installation Guide
15
Risk of electric shock through contact with live wires!
Use separate ground wires to provide protective grounding (PE) for the OpenScape
Branch 550 / 550HA communication system and possibly any main distribution frames
being used. Connect your communication system and your main distribution frame to
the ground wire before starting up the system and connecting telephones and lines.
Make sure that the ground wires laid are protected and strain relieved.
NOTE: A figure showing the assembly of the protection ground terminal is to be
provided.
Lightning Protection Requirements
The protection of communication system against high-energy surges requires a low-
impedance ground connection.
Once a communication system has been grounded, check the low-impedance
ground connection of the system using the ground conductor of the mains power
supply circuit and the low-impedance connection (of the additional permanently
connected protective ground conductor) to the building's potential equalization bus.
Fire hazard due to surge voltage!
Telecom lines which are over 500m in length or which must leave the building must be
conducted through an additional external lightning protection.
Lightning protection of this kind is known as additional primary protection. The
additional primary protection is guaranteed by the professional installation of ÜSAGs
(surge arresters, gas filled) in the main distribution frame, the patch panel or at the
entry point of the pipe in the building. A gas-filled surge arrester with 230 V nominal
voltage is switched to ground from each wire that is to be protected.
Without this additional primary protection, lightning could irreparably damage the
telecom boards. This can cause the entire communication system to fail or result in
components overheating (fire hazard).
Connecting to the Power Supply Circuit
The communication system has been approved for connection to TN-S power supply
systems. They can also be connected to a TN-C-S power supply system in which the
PEN conductor is divided into a ground wire and a neutral wire. TN-S and TN-C-S
systems are defined in the IEC 60364-1 and IEC60364-5-51 standard.
Risk of electric shock through contact with live wires!
Only qualified electricians should perform any work that may be required on the low-
voltage network. These installation activities to connect the communication system
must be performed in compliance with IEC 60364-1 and IEC 60364-4-41 or any
corresponding legal norms or national regulations.
