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#61 Re: PSU designer understanding.

Posted: Fri May 01, 2020 11:56 pm
by IslandPink
pre65 wrote: Thu Apr 30, 2020 9:12 pm The first caps are MKP low inductance 5uf. Un = 1200v, Umax = 1680v ESR = 1.1Mw (?) Irms = 64A
Is that output from PSUD or the info you input on the caps.
ESR would be in mOhms, and is a user input.

#62 Re: PSU designer understanding.

Posted: Sat May 02, 2020 11:27 am
by pre65
The Mw was from the capacitor data sheet, and the question mark was because I didn't understand why it was not denoted in ohms.

I know that if one puts the correct user data in PSUD the results are more accurate.

#63 Re: PSU designer understanding.

Posted: Tue May 05, 2020 7:15 pm
by IslandPink
It's possible the 'w' was supposed to be the Greek omega , but there was a font fail somewhere ( lost in translation )

#64 Re: PSU designer understanding.

Posted: Fri May 08, 2020 3:08 pm
by Mike H
Image

1.1 mΩ then.

#65 Re: PSU designer understanding.

Posted: Fri May 08, 2020 3:09 pm
by pre65
Mike H wrote: Fri May 08, 2020 3:08 pm Image

1.1 mΩ then.
That's what I'm going for.

#66 Re: PSU designer understanding.

Posted: Fri May 08, 2020 3:24 pm
by Mike H
What's the default in PSUD? I seem to remember 2 milli-Ohm?

#67 Re: PSU designer understanding.

Posted: Fri May 08, 2020 3:28 pm
by pre65
Mike H wrote: Fri May 08, 2020 3:24 pm What's the default in PSUD? I seem to remember 2 milli-Ohm?
More like 2 Ohm.

#68 Re: PSU designer understanding.

Posted: Fri May 08, 2020 6:55 pm
by Mike H
Thanks, knew it was 2 something! :lol:

#69 Re: PSU designer understanding.

Posted: Wed May 13, 2020 11:50 pm
by pre65
Whilst composing a long post (now deleted) I came to a conclusion.

Forget 811a A2 for the time being, and concentrate on getting 833a back up and running.

It would mean borrowing the major parts of the GK-71 monoblock amps power supply, but they have not been used for ages, so no great loss.

It's late, so I'll sleep on it.

*

#70 Re: PSU designer understanding.

Posted: Wed May 20, 2020 5:20 pm
by pre65
I was sat here this morning thinking about 833a and the mains transformers, and I postulated on how the Hammond 735A might measure up if I connected the 234V AC primary windings to the 120V output of an isolation transformer.

Would the secondary voltage come down by the same ratio as the primary, and what about the VA rating ?

My brain hurts thinking about it. :? :oops:

Hammond 735A data sheet.

https://www.hammfg.com/files/parts/pdf/735A.pdf

#71 Re: PSU designer understanding.

Posted: Thu May 21, 2020 11:42 am
by pre65
I can't delete the above post, so please, just ignore it. :oops: