Grunff wrote:

If I'm going to go down the data logger route, I will probably go for

one of these:
http://www.audon.co.uk/labjack.html

I used one before in a previous project, and found it to be a very
nice
piece of kit.

But that wasn't my question really - I can see how to get the
measurement I want by sampling V and I with a data logger - but I
can't
help wondering if there isn't a cleverer, simpler way, given that all
I
want is total energy.

Another way of asking the question - I can see how to integrate the
data
electronically, after collecting a huge number of data points. But
I'm
wondering if there isn't another way of doing the integration. If
that
makes sense.


--
Grunff

there is, use an opamp integrator. No sampling, along with the errors
that introduces.

NT