Telecommunications and data transmission devices (PABX, modems, data terminals etc..) are becoming increasingly vulnerable to lightning-induced voltage surges.
These devices are becoming more complex and are currently connected to several networks : this situation increases the risk for these sensitive devices to be stressed by destructive surge voltages, induced by lightning or by electrical switching operations.
Moreover, these devices are nowadays installed at every level of every installation (industry and business buildings, residential houses and buildings), making their possible disturbances unacceptable or/and costly.
To make this telecom or data equipment sufficiently reliable, the installation of dedicated surge protectors, against transient overvoltages, are highly recommended.
Reminder:
Devices connected to telecom or data networks, are also connected to the AC distribution network : in order to ensure a relevant protection, surge protectors must be also used on these supply networks.
Installation of surge protectors on data-processing networks could be necessary, specially in
the following cases :
Inter-building networks
Wide networks
High Electromagnetic disturbance density
As for the other types of transmission lines, the surge protectors for Local Area Networks (LANs) are based on association tripolar gas tubes and fast clamping diodes to ensure efficiency on lightning surges.
However, two additional parameters are to be taken into account: very low transmission voltage and high bit rate of the transmission.