The Blog of Ian Mercer.

A smart power strip

Cover Image for A smart power strip

Recently I added a smart power strip to the TV/Amplifier setup in the living room. My main aim was convenience - to make it easier to turn everything off all at once. But I also wanted to see how much power I could save by eliminating the parasitic power drain that a TV, amplifier and two DVD players have when in the 'off' state.

The power strip I bought is the one featured to the right here and to date I'm pretty happy with how it's working. The power strip has one 'blue' outlet that senses when a single device goes on or off and then several 'green' outlets that switch accordingly. Initially I plugged the amplifier into the sensing output and everything else into the green outlets. That worked great and when the amplifier goes off so does the TV, the DVD player and the DVD changer. Since the amplifier is a Denon -CI model I can also control it remotely and since everything else switches on and off with it I can remotely shut down the whole stack from my home automation software.

The only problem with that approach is that in the 'off' mode the Denon -CI still consumes about 5W whereas the TV consumes 0W when off. The TV is one of the earliest HD TVs, a Panasonic Tau CRT TV so it's fairly power hungry when on but it has a 'real' on/off switch so when it's off there is no power draw at all. [Until recently the picture on that CRT beat nearly every flat panel TV on the market, but with recent LED LCD TVs I think I may finally be willing to part with it. It's old technology, but still an awesome HD picture.] So now I have to chose between remote power-off control and a 5W constant draw or no remote control and 0W consumption.

When I purchased the smart power strip I was concerned that it might itself have a phantom power drain equivalent to one of the other devices but it appears to be relatively harmless consuming hardly any current for itself.

The one adjustment you need to make on the smart power strip is to set the sensitivity so it can turn on and off at the right point.

Overall, definitely a recommended buy on this one.

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