Grunff wrote:
mark wrote:

1. Assume a constant mains supply voltage & frequency


It's a regulated DC power supply.

OK. Depends on how good the regulation is as to whether
this assumption holds. Does it sag a bit?


2. Using a True RMS meter with peak avg/min/max record
facility, measure the current.


It's DC.


The current isn't static is it? It's a spikey load.
There will still be a min/max/avg figure even for DC.


3. Compute the avg/min/max power from the meter readings
and assumed supply voltage.



But the rest is spot on ;-)



thanks
Mark.