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John Rumm John Rumm is offline
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Default Measuring power consumption of immersion heater?

wrote:

Are you suggesting that the Aldi power meter is not a power meter?

No, what I was highlighting is that the write up for it offers no clues
as whether it is able to distinguish between real and apparent power
consumption[1] - so take readings taken on this sort of kit with a good
degree of scepticism.



I'm afraid I don't fully understand. A device consuming 20W will do so
irrespective of the power factor. A power meter should measure this
power, just as my electricity meter does. What does making allowances
for pf mean?


The simplest ones measure the line voltage and the current flow and from
that deduce the power consumption. On kit with non unity power factors
this will end up reporting the VA rating rather than the real power
consumption.


--
Cheers,

John.

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