The adapter has three indicator lights, labeled PWR, LK, and ETH for Power, Link, and Ethernet, respectively. When all of the lights are green, it generally means everything is in excellent condition.
There's not a whole lot to setting up a power line connection, and that goes for the TPL-406E as well. If your network is already power line connection-ready, just plug a TPL-406E into a wall socket, then connect a wired device to it using a network cable (the adapter comes with one network cable included), and you're done.
If this is your first power line connection, you'll need two units. First you hook up one of the adapters to the network via the router (or the switch), using a network cable. The second adapter is connected to an Ethernet-ready device, such as a printer, at, say, the far end of the house. After that, you just plug both adapters into the power sockets. And that's it. Basically a power line connection is an alternative to running a long network cable between the router and the Ethernet-ready device. In the case of the TPL-406E it's actually much cheaper to get two units than to run network cable properly. This is because running a cable behind the wall involves the cost of the cable, the two network wall ports, and.
If for some reason you find the above steps complicated, both the TPL-406E adapter and the TPL-406E2K kit come with a very detailed setup poster.
As mentioned above, since it's bottlenecked by the Ethernet standard of its network port, the TPL-406E adapter can't offer the speed of Powerline AV 500, but it did show the top Ethernet performance, which is 100Mbps. I used two TPL-406E adapters for testing and they consistently scored 90Mbps. This was basically as fast as a normal Ethernet connection can get after taking overhead into account.
For a such a small and low-cost device, I consider this performance excellent. Note that this is the sustained speed; that means it's faster than most Wi-Fi connections. On top of that a power-line connection is a lot stabler than a wireless connection and has much lower latency.
(Longer bars indicate better performance)
Tiny, affordable, and as fast as 10/100 Ethernet can get, the Trendnet Powerline 500 AV Nano Adapter (model TPL-406E) is an excellent buy if you want to extend your network via power line networking, especially when you buy the kit of two units. If you were planning on running network cable from one room to another, the TPL-406E2K kit actually costs less in terms of hardware and takes just a few minutes to get the job done.