How does a powerline adapter work?

If you absolutely need a real, wired ethernet connection in a room far away from your router, a powerline adapter is a great choice. In many cases, all it takes is plugging two boxes into wall outlets, wiring one to the router and one to your device and you’re all set. But how does it work?

There are really two things that you need to realize about the way your home is wired, and both of them contribute to powerline networking.

First, your home’s electrical system is made of copper wire. Lots of it. Not only that but it’s actually really thick, high-quality copper wire. It has to be in order to deal with all the stuff you plug in, and all the electricity you want for all your cool stuff. You know what else is made of copper wire? Signal cables. Signal cables (like ethernet cables and coax cables) are thinner because they don’t need to be thick (put a pin in that, we’ll get there.) So it’s not a big stretch to think that you could put network information over your home’s power system.

Second, unless you have a pretty fancy home, the power lines are pretty “noisy.” In other words, the voltage levels surge and dip a bit all the time. Most electrical devices are designed to deal with a small amount of interference on a line and slightly varying current levels. Deal with, yes. Ignore, yes. But what if you could harness that “noise” to your advantage? Encode information onto it? That’s exactly what powerline adapters do. They introduce a signal onto the electrical wire that most of your appliances interpret as just more harmless noise, but that powerline adapter on the other side of the house sees it as precious network information. That’s the magic of a powerline adapter.

Remember when I said network cables don’t have to be very thick? There’s a very peculiar property of signals as they travel over a wire. They don’t actually travel all the way through the wire. They just sit on the very outer edge. So, signal cables can be thin because nothing travels on the inside anyway. On the other hand, electrical current travels all the way through the wire. That’s another reason that signal and current don’t really bother each other, because they inhabit different parts of the cable.

Now, it’s probably fair to tell you that powerline networking doesn’t always work. If your power lines are too noisy, for example due to old-school fluorescent fixtures, you’ll have problems. If you have multiple circuit breaker boxes they probably won’t work at all. And if the wiring in your wall is built with surge protectors in it, even simple passive ones, you won’t get the results you want. But really most people have great experiences with powerline adapters and there’s a very good chance you will as well.

Try a set of powerline adapters from Solid Signal and you’ll realize that you don’t have to worry about expensive Ethernet cabling. They’re fast, easy, and now you know how they work.