Andy Wade wrote:
Ian Stirling wrote:

The maplin one I have misreads in a similar way to the Lidl ones.

What way is that - and how much in error? (Genuine questions.) I have a
Maplin one and whilst I haven't rigorously assessed its accuracy it does
give quite plausible readings on low consumption low PF loads (such as
CFLs).

Double - on 3 similar PC power supplies.
I was concerned, as it was reading my PC with one drive and no monitor at
100W, which seemed unlikely.
A few minutes later with a few resistors and a scope, produced waveforms
for current, which looked rather odd, and seem to be the reason it misreads.
These things will only sample the current so often, and it seems not quite
often enough for some loads, so they make mistakes.

(For all other devices including various sizes of SMPS it worked fine)