SurgeArrest will warn you if its circuitry has been damaged by heavy strike or power line surge and it is unable to provide 100% protection.
Protection of data lines (Ethernet, Coaxial and Phone lines) ensures complete protection of your equipment from surges. It is very important to protect your equipment from "back door" electric surges traveling through data lines, as they can be as damaging to your equipment as surges traveling over power lines.