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Minimum current draw of AC to DC converter at no load

bobdxcool

Mar 9, 2012
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Mar 9, 2012
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I wanted to know if there is a minimum current draw on the AC to DC converters from the AC source when it is connected to an input voltage of 120V (60Hz), when no load is connected at the output of the converter ? Is this current draw constant ?

For example, if we consider this converter from progressive
dynamics,

http://www.progressivedyn.com/power_converters_9100.html

If we consider the PD 9180, would there be any current draw from the AC source for this converter ?
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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There will always be some minimum if the device is powered on. However this minimum could vary from almost immeasurable to a significant percentage of the full load current.

Unless it's in the specifications, I would either ask the manufacturer or get one and measure it.
 

davenn

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Sep 5, 2009
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hi Bob

generally yes there is a very small current maybe in the order of a few mA for a wallwart switching regulator plugpack
and most likely increases as the SMPS increases in its ratings

to find out for any given SMPS, you would have to ask the specific manufacturer

there is a cool device called Kill-A-Watt a small unit that plugs into the wall outlet and then your device plugs into it and it displays Wattage etc being used

Dave
 

Colin Mitchell

Aug 31, 2014
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Some of them have a special circuit to reduce the idle current to 10mA or less and it looks for something connected to the output.
Some 4kW inverters drop to 10mA.
 
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