> So can someone clear up two points, why do I remember
> being taught about RMS=average (20 years ago now!),

Your instructor may have been confused.

> is this true for sinewaves maybe?

No, sorry.

> And if I get voltage samples and use the RMS calc to
> get the overall RMS value of the volts, would this
> be usable to calc power in a load directly??

Yes, if the load is resistive and the resistance is known.

> What if the load was inductive or capacitive?

Then it depends on frequency too.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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