Protecting Your Laptop During Thunderstorms: Lightning & Ethernet Risks

[Rach3]

Suppose I have a laptop on battery power, connected to a network router which is AC powered, during a thunderstorm. Will a voltage spike at the router cause any damage to my laptop NIC?

 

[chroot]

It certainly could, but it's not very likely, either.

A lot of devices would have to fail in some very specific ways (the wall transformer, the regulators on the router's circuit board, the drivers on the transceiver IC, etc.) to permit a large voltage spike onto the ethernet cable. The majority of the time, the lightning strike would essentially vaporize one of these components, creating an open circuit that would limit its damage. This could be called "failing open."

Futhermore, the actual ethernet line drivers in your router are on an integrated circuit. They connect to the outside world through very tiny gold bond wires, each smaller in diameter than a human hair. They cannot carry much current at all before vaporizing, so it's not very likely that a significant amount of charge could be pumped through the driver before it fails open.

On the other end, your laptop's NIC has an ethernet transciever with a lot of ESD protection built into it, including snap-backs or clamps and beefy diodes. They would probably happily absorb any voltage spike that comes through the ethernet cable, given that the transciever on the other end is rather self-limiting -- it would fail open before it could transmit much charge.

- Warren

 

[ravenprp]

Yes, a voltage spike at the router during a thunderstorm can potentially cause damage to your laptop's NIC (Network Interface Card). This is because the router is connected to the laptop via an Ethernet cable, which carries electrical signals. If there is a surge in voltage at the router, it can travel through the Ethernet cable and reach your laptop, potentially damaging the NIC.

To protect your laptop from such risks, it is important to use surge protectors for both your laptop and the router. Surge protectors are designed to absorb and redirect excess voltage, protecting your devices from damage. It is also recommended to unplug your laptop from the router during thunderstorms to further reduce the risk of damage.

Additionally, it is important to regularly backup your important files and documents in case of any unexpected damage to your laptop. This will ensure that your data is safe and can be easily recovered if needed.

In summary, it is important to take precautions to protect your laptop during thunderstorms, including using surge protectors and backing up important data. By doing so, you can minimize the risk of damage to your laptop's NIC and ensure its longevity.