On 1/21/2010 10:30 PM, Forrest Christian wrote:
> On 1/21/10 3:15 PM, Dwayne Reid wrote:
>> Because we are operating the transformer with such reduced input
>> voltage (less than a third of rated input), linearity is absolutely
>> NOT a problem.
>>
> I take it the linearity issue really only occurs when the magnetics
> saturate... which of course would be around the rated voltage.
>
> I like the idea of running a transformer at half it's rated voltage (or
> thereabouts) to keep the saturation from occuring.  One of my 'blind
> areas' - I don't even think about running things outside their expected
> voltage range.

Power transformers are not designed to saturate at rated voltage.  One 
that does would get very hot very quick.  When saturation occurs, the 
impedance that the primary presents to the incoming line drops towards 
zero - all you get is Rdc of the primary winding.  Input current then is 
Vapplied/Rdc; usually a very big number of amps.

Although that is the case, as Dwayne points out, running at half the 
rated value will promote longevity of the transformer as it will run 
cooler as well.  Linearity should be excellent.
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