Keith D said the following on 25/07/2006 21:47:
I would like to have a data logger that can track the KWs being used in my
home. I need to know load times/days etc. I have seen a number of items that
do this by attaching to the power cable from the consumer unit and then
sending this data using RF to a display unit.
(http://www.electrisave.co.uk/) but this does not have a PC interface so I
cannot use it to log data over a long period of time.
Question: How does this device collect/measure the total electricity used?


It has a sensor that you connect around the live wire of your meter
tails that measures the current flowing in the wire. The sensor
transmits the signal to the receiver (as shown in the photographs on the
above website) and the receiver (which you programme for the nominal
voltage of the mains) then calculates the power being consumed by the
whole house. This is an instantaneous (or maybe average) reading and
the unit does not appear to do any data logging at all.

See he http://www.abc.net.au/ra/innovations...es/s965886.htm


If I wasn't prepared to pay for something really expensive

I would consider using one of these: -

http://www.sjelectronics.co.uk/acatalog/RR3020-30.pdf

and something from this company: -

http://www.picotech.com/data-logger.html