In Reply to: RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell posted by Paul Joppa on August 29, 2020 at 16:07:40:
A 58mA RMS rated secondary seems low for 50mA DC, CT, C-input tube rectified power supply. For 50mA DC draw I'd expect to see 70mA RMS, or greater.
The JE Labs design quoted would likely have 65-70mA RMS on the B+ secondary, which exceeds the 58mA RMS rating.
I don't like to run transformers near their maximum ratings; I'd be more comfortable with a secondary rated for > =80mA RMS. I also like to de-rate the power transformer's VAC by 50% (or more) for cooler running and perhaps lower noise and longer life.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
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Follow Ups
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - 91derlust 08/30/2015:04:19 08/30/20 (5)
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - Paul Joppa 17:08:54 08/30/20 (4)
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - 91derlust 17:48:28 08/30/20 (3)
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - Paul Joppa 23:10:32 08/30/20 (2)
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - 91derlust 13:01:12 08/31/20 (0)
- RE: New project, voltage checks good, blows fuse after 45 minutes and power transformer hellaciously hot and odd smell - kobasa@xs4all.nl 00:03:37 08/31/20 (0)