@loughside 

Downed power lines can cause power outages. Before the power goes out, though, voltage along power lines often fluctuates wildly, which causes dangerous power surges.

When larger appliances in your home (like your AC) shut off, all the electricity it had been receiving suddenly has nowhere to go. This results in a very brief increase in voltage throughout your home’s wiring. Anything hooked up to your home’s electrical system can be damaged by this surge.

Surge protectors work by monitoring the amount of voltage that flows along wiring. If it detects a dangerous spike in voltage, the surge protector immediately diverts the extra voltage into the earth via a “ground wire.”

Point-of-use (POS) surge protectors are designed to protect one (or more) appliances. POS surge protectors are installed between the outlet and the appliance(s) it protects.

These surge protectors help catch any leftover voltage from larger internal power surges before it reaches your electronics. The good news is that these surge protectors don’t require professional installation. In fact, you can find point-of-use surge protectors at most general stores and can install them easily on your own.

In addition most of the home UPS devices except the uninterrrupted power supply include surge protection on their power outlets as well.

  @loughside 

A lightnning storm theoretically can harm VR400 via its DSL or ethernet ports as well, but fibre cable cut shouldn't have caused any harm to this device.

How did you test the ethernet port and conclude it's not working ?

  @loughside 

Hi, thanks for posting question here.

It is suggested to contact local retailer or support to confirm compliance with warranty policy.