Thursday, 15 March 2012

Feel the Power!

On Sunday I installed the LightwaveRF power meter. The picture below shows it outside it's lovely packaging. The power meter consists of two main parts. The clamp that goes around your live AC feed (on the right in the picture) and the sender unit (on the left). In simple terms the clamp measures the power usage and the sender sends the measurements to the WiFi link unit. The sender unit takes 2 AA batteries and sends a measurement every 10 seconds.
Here's a close up of the clamp. It looks to have some form of magnet inside. I'm not clamp meter expert so see Wikipedia for an explanation of how they work!

Here it is installed in my meter cupboard, clamped aroind my live AC feed. The sender unit nestles on the bottom.

To pair with the WiFi link you just put the sender into learning mode (press and hold a button) and select an option on the UI of the WiFi link. When paired you get the latest reading from the sender always shown on the WiFi link screen.

You can view the measurements on the web interface or via the handset app (example shown below):

You get:

1)Current power consumption (in kW).

2)Max usage for the past 24 hours (in kW I assume but no units shown - naughty).

3)Cumulative usage that day (in kW Hours I assume but no units shown).

4)Total usage yesterday (I assum ein kW hours).

The dial refreshes every 10 seconds or so with a bit of animation, very nice. The warning states it could be 20 secs out of date which is about right in practise. Flick the kettle on and the dial goes up to about 3.5kW within a short period of time, (off the scale of the app UI in fact which is a bit poor).

More later on the energy meter...