The TP-Link AV500 Powerline Adapter with AC Pass Through (TL-PA451KIT) is a neat set of two Powerline adaptors that performed very well in our real-world tests but, like all other Powerline adapters, doesn't get anywhere near close the claimed 500Mbps speed.
If you read our article What Is Powerline, which explodes the Powerline speed myths, you'll understand that Powerline manufacturers boast of theoretical maximum speeds that are impossible to attain. No matter, as the speeds achieved in reality are far faster than if you relied on so-so Wi-Fi speeds to connect your smart TV, games consoles, Sky+, Tivo, Apple TV and other set-top boxes.
Powerline works its magic by using your house's power cables as extensions of the Ethernet cable you connect from the router to the base adapter, and from the second adapter to your digital device, as listed above.
The TP-Link AV500 Powerline Adapter with AC Pass Through might have a long-winded name buti nstallation is simple. You simply plug one into a power socket near your router, and the other in the second room where you desire the faster-than-WiFi network speeds.
The AV500 also features pass-through sockets so you don't use up each of the valuable power sockets the adapters are plugged into.
There's only one Ethernet port on the bottom of each adapter, so you'll need to swap out the Ethernet cable – two are included with the two adapters – if you have more than one device that requires the fast network speeds. Also it uses the slower 10/100 Ethernet so the theoretical maximum is really just 100Mbps not 500Mbps. But TP-Link is not alone in labelling this class of Powerline as 500Mbps.
The lack of Wi-Fi makes it a little over priced, but you do get fast speed and that pass-through socket lacking on many Powerline adapters.
Update: TP-Link now has a very similar model (the TP-Link AV500 Passthrough Powerline WiFi Kit) with three Ethernet ports and the ability to add a new Wi-Fi hotspot to your second room.
Powerline testing procedure
We tested the TP-Link AV500 Powerline Adapter in a Victorian house with fairly old wiring and the usual array of electronic devices (TV, Sky+, Hi-Fi, lamps, microwave, computers, etc) plugged into the power lines. The Internet router was situated in the office on the second floor, and we used Powerline to test data speed on the ground floor.
If your house was built more recently you may well achieve faster speeds than we did, but we use this house to get consistent speeds for a proper Powerline comparison.
First we must emphasise that despite all the Powerline manufacturers claiming 500Mbps speeds these are theoretical maximums, and you will never see such speeds via Powerline. Indeed the 10/100 ethernet port limits the maximum speed to 100Mbps. You'll be lucky to get 100Mbps from a 500Mbps Powerline, but don't fret as this is well fast enough for most needs, such as watching catch-up TV or downloading fairly large files. And rest assured it's much, much faster than standard home Wi-Fi.
We got speeds up to 93Mbps but the house average was 68Mbps using Powerline and ethernet. This was actually one of the fastest speeds we got in our comparison of Powerline over ethernet, and will be sufficient for most users – we downloaded HD TV with few pauses.
Check out all our Powerline adapter reviews and also our group test of the best Powerline adapters we've tested. You can get more information on Powerline including explanations of Powerline speed myths and lots of tips and trick in our feature What Is Powerline.