When we think of the ways in which we can protect our electronics from a lightning strike, or from an electromagnetic pulse (EMP), one of the most effective methods is to build a Faraday cage. A Faraday cage is an enclosure made of conductive material that blocks electromagnetic fields. It’s named after Michael Faraday, who discovered the principle of electromagnetic induction in 1831. Induction is when a changing magnetic field induces an electric field; in other words, it causes electrons to move.
You might be familiar with wireless charging, in which a device coils up close to a special coil due to an attached USB-C wire. This causes an induction to happen between the two ends of the cable. Once the device is charged, the wire can simply be removed. This wire can also be inductively coupled to other devices, like a phone, with a simple circuit, making it a wireless charger. However, when the device is in use or charging, it introduces additional magnetic fields throughout its entire body, and these forms of inductive coupling can strengthen the electromagnetic pulse that can damage electronics.
The best way to avoid this danger is grounding your electronics, meaning disconnecting or disconnecting the charging source from the rest of your electrical devices. For example, a PC can take one of three forms. One port can charge wireless devices and accessories (like headphones) along with the rest of the cable. If the PC is placed near a router, unfortunately, wireless charging is almost impossible due to the proximity of the router and other electrical devices. To use a cable, the PC would need to be plug-and-play.
Another port could be used for charging items that don’t need a cable, like flash drives. And for a laptop, USB-C would be the only port plugged in. This port makes up most of a laptop’s ports, so connecting anything else would be impossible. There is a third port, which is usually called a port on the side, such as the one for a space heater or portable HD player. This port is connected to the main power port on the wall, allowing it to operate independently at a moment’s notice. There may be more than one way to define this port, but the important thing to remember is that the port itself should never be connected to an animal or living creature. Connecting a wire to an animal would be a major hazard.
If you need a laptop, it will be possible to recharge it wirelessly. However, if you don’t have other options, you can purchase a charging cable to plug into a wall outlet or power strip. Just like in a regular house, it’s important to thoroughly clean electronic devices to reduce the chances of environmental contamination. dirty keyboards, old keyboards, broken screens, scratched screens—you name it.
These are just a few examples of what can be happening in your electronics once they get old and rusted. If they get stuck in an equipment tripwire, then they’re at even greater risk.
Faraday cages are built to withstand a strong electrical charge, which would otherwise destroy electronic devices. While a traditional padlock can take 3,000 cycles to break, a Faraday cage can withstand an infinite number of charge/discharge cycles. This means that when we power up our laptop, or when we plug our phone into an outlet, the electric field will flip the polarity of the conductor in the small enclosure, effectively creating an infinite barrier between the computer or device and the outside world. The faster the computer or phone is charged, the stronger this barrier is.
One of the advantages of a Faraday cage is the fact that the enclosure can completely isolate the device from the outside world. Our current laptops or phones are connected to the internet, and since the cells communicate over WiFi, which not only allows for internet access, but also allows for advertisements, credit card reading, and even tracking, it is easy to see how easy it would be to introduce an electromagnetic pulse into a shielded enclosure, like our laptops, and turn it against us.
We have seen a lot of fringe, and even outright wrong, incidents that have brought a bit more skepticism into the topic of grounding our electronics. At the Surface Laptop launch event, Microsoft mentioned a TV that got fried when an electrical circuit shorted while charging a laptop. That machine also had a padlock on it, for good measure. We also saw a mobile phone charging with a screw, … which was promptly smushed by a large rock that also had a padlock on it.
There are two problems with these incidents. First, it is highly unusual for a laptop to actually short itself out in the middle of charging. The charging process is so fast, and there are two ports running current at the same time, that it would usually be nearly impossible to short anything out in that short time frame. Secondly, the second incident was noted months after the first and reported that shortly after that a separate rock had jammed the charging port on a mobile phone. It doesn’t sound like the damage here was caused by a lightning strike, or by a user attempting to short something.
These two incidents, taken together, leave a lot more questions than answers. For one, charging through a metal or plastic object makes little sense.