Transformer Rating

The VS (Volt Second) rating of a transformer specifys the maximum product of applied voltage multiplied by time in seconds before the transformer core saturates. 10V for 1uS is 10uVS and 20V for 1/2uS is also 10uVS. If 10uVS are applied to a transformer winding, magnetizing flux builds in the core relative to the VS product, that flux must not exceed the saturation level of the core or the winding will start to look like a short circuit. After a the voltage is removed the core must be reset by the application of the same VS with reverse polarity, AC signals continuosly reset the core. For square wave or pulse application VS is simply the Voltage times the pulse width. For sine or other waveforms the VS product is the area under the VS curve, calculated by integrating the wave form between zero crossing points. If the +/- volt seconds are not equal the transformer can walk towards saturaion.

I'm wondering whether the questioner has made a typo and the question should be the VA rating??

John.

DEAR I M RALLY ASKING FOR VS RATING i saw it on an industrial xmer

Guest #1 gave a very good and complete answer to your question.