The NIST surge guide says (page 14):
"Intruder alarm systems using wires between sensors and their central control unit can be disturbed - and damaged in severe cases - by lightning striking close to the house. The wires necessary for this type of installation extend to all points of the house and act as an antenna system that collects energy from the field generated by the lightning strike, and protection should be included in the design of the system, rather than added later by the owner."
Sounds kinda like MadAlex
Near lightning strikes can directly induce voltages with wires acting as "long wire" or "loop" antennas.
Protection of incoming cable is through a ground block that connects the cable shield to the building earthing system.
The IEEE guide says “there is no requirement to limit the voltage developed between the core and the sheath. .... The only voltage limit is the breakdown of the F connectors, typically ~2–4 kV.” And "there is obviously the possibility of damage to TV tuners and cable modems from the very high voltages that can be developed, especially from nearby lightning."


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