UPS buying suggestion
ralf.mardorf at alice-dsl.net
Tue Oct 15 13:19:23 UTC 2013
On Tue, 2013-10-15 at 20:16 +0800, Erich Dollansky wrote:
> 'For what are known as "reactive loads" the answer is no. Reactive l'
> A PC is a reactive load.
You're doing the measurement for a while and then you win an impression
of the consumption.
Reactive power compensation can reduce the reactive power, however, your
electricity provider only will measure the active energy, only for large
customers they will measure the reactive energy.
IIUC the OP want's to get a raw impression of what is needed and isn't
interested in rocket science.
> > Anyway, you can't trust those power meters.
> Do not think so bad. It is all a matter of price.
Yes, you need a rotary current meter, like the once your electricity
provider installed to your home, or you turn off everything at home,
excepted of the computer and check the consumption by this meter. If you
want to have more precision, ask them to install a device to measure the
reactive power too ;).
For electronics usually the rule of three and rule of thumb are used, by
ignoring internal resistance of one or the other source, tolerances of
one or the other component, phi etc. pp.. But there is more math than
just the rule of three available, for theoretical usage and perhaps
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