Toroid Transformer Amp Rating, No Datasheet

Hello All,

I am using a surplus toroid for my PSU build and want to verify my math to determine amperage rating.....

It has dual secondaries for 40-0-40v @ 700VA

Lacking the data sheet I have calculated 8.75A as follows:

700VA / (2x40v) = 8.75A

Is my formula correct? If not, please direct me to where I might find the information.

Cheers,

David
 
Yes, that is close enough for any such purpose, in round numbers 9A per secondary.

It'll be a chunky beast! Given that you'll see c 55-56Vdc after rectification it's enough VA to more than support the full c.160W rms /8ohms /channel you'd get for using it powering a stereo amp; and it'll not blink at delivering a potential full 300W rms into 4 ohms x 2channels either.
 
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Thank you for the help Martin. Now I know I can use the 25A / 400v rectifier I have laying around for my first DIY Amp, a 2-channel designed by Rod Elliot. Looking for a solid 150 watts into 8 ohms. I did not build the enclosure myself, but I have learned so much in the process that I owe it to myself to have it look good too.

IMG_7078.jpg

Cheers,

David