Coordination between surge arresters for energy networks and those for other installations
Surge Protective Devices. Description. Installation

When a system has been effectively protected, all its inputs are protected by surge arresters to achieve equipotentiality between the structure, its installations and the SPF (the latter may be the structure itself when it is capable of accepting this constraint).

We have seen that it is sometimes necessary to install additional surge arresters close to sensitive equipment. However, this is not always sufficient.

In the case of an installation where the energy network and the telephone network (for example) are not connected to the same earthing system, or when they are connected to the same earthing system but not at the same point, in the event of a lightning strike on one or other of the networks, a high overvoltage can still be generated at the terminals of equipment connected to both networks, such as a modem in the example shown in...