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Phil Allison Phil Allison is offline
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Default Low Frequency Mains Noise

"Patrick Turner"

When I measure the "240Vac" here is usually is stable enough to get a
nearly constant reading on a DMM,


** Must be a basic 3.5 digit one ( 2000 count) with only 1 volt
resolution
when reading 240 volts AC.

Any DMM with a larger count allows changes of 0.1 volts to be seen -
then the last digit is never steady.


Indeed, I'll get 240.XX Vac maybe even 24X.XX if the voltage is just
either side of 240.0Vac.

That's less than 1% Vac change.



** Another completely irrelevant reply.

Yawnnnnnnnnnnnnnn ...


But it slowly varies between 235Vac on cold winter nights of heavy
loadings to 255Vac when load is light.


** What drivel.


Not so, this is without changing local loads here in my shed.



** Another irrelevant reply.


Rarely does the mains ever bounce rapidly between 235Vac and 255Vac.



** More irrelevance - since I never claimed it did.


It will instantly drop by 7 or 8 volts if you switch a ( 2.4 kW) electric
heater on AND jumps up by 6 volts when the ( 2kW) jug turns itself
off
when it has boiled.


Not necessarily so.



** Now that IS a blatant lie.

Anyone can try it and see what happens to the AC voltage on the same
circuit.



When I look at the rectified Vdc, it shows the expected variations of
+/- 30mV.


** Complete ********.


No.


** Another BLATANT lie.


Any unregulated DC supply FOLLOWS all variations in the AC voltage by
the
same percentage.


Agreed.



** Then stop posting ****ING STUPID **** that says otherwise.

You misunderstand me.



** NO - you completely misunderstand the point.



..... Phil