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How to determine the VA rating of an AC transformer?

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Lucifre

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I bought an ac transformer from radio shack... now there is no va rating specified. i was wondering if there is any way to determine it from the specs given and they are listed below

12.6 VAC, 300 mA PC Board Transformer
Input: 120 VAC, 60 Hz
Output (load) 12.6VAC @ 300 mA ± 5%
Output (no load) 16.38VAC ± 5%
Current (load) 90 mA max
Current (no load) 60 mA max

to get VA rating do i just multiply current times voltage? also, what are those currents with load and no load? Can i get data sheet for it?
 

IanP

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Re: Transformer Help

You can look at these number as follows:

12.6V @ 300mA but 16V @ no load --> the output voltage without load will be ≈16Vac and will drop down to 12.6V with load current of 300mA ..

90mA (load) max --> max primary (120V side) current with the secondary load of 300mA ..
60mA (no load) max --> max primary current without load connected to secondary ..

VA rating will be ≈ 12.6V * 0.3A < 4VA

Regards,
IanP
 

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