Yes, I must admit that I've found the 10R thermistors quite adequate for the task but I do use the dc trap for anything bigger than 200va torroidal transformer these days - this, plus the Haggerman snubbers (C, R+C) on the secondaries and a well thought out C-Mx is a pretty good combination.
Some years ago (more than I want to think!) I built a big 250W classAB amp to drive troublesome speakers like the dastardly Infinities, etc - these were the days when large EI transformers were the rule - the damn thing weighed about 40kg - biased about 10W classA, valve gain stage, fan cooled, 10 o/p TO3 trannies/ch - a monster that worked extremely well - I think I'd have a serious hard look at the switchmode supplies these days with the appropriate filters
Some years ago (more than I want to think!) I built a big 250W classAB amp to drive troublesome speakers like the dastardly Infinities, etc - these were the days when large EI transformers were the rule - the damn thing weighed about 40kg - biased about 10W classA, valve gain stage, fan cooled, 10 o/p TO3 trannies/ch - a monster that worked extremely well - I think I'd have a serious hard look at the switchmode supplies these days with the appropriate filters
I use a mains soft start on all transformers from 100VA upwards.
I fuse all my transformers to close rated spec, if the very low value fuses are available.
Take the 100VA on a 240Vac supply. The close rated fuse would be 0.42A. I use a T500mA
Adding a 140r bank of resistors prevents that small fuse from blowing on repeated cold starts.
80VA and lower have a high resistance primary that is in effect a current limiter during start up.
I use an F500mA to fuse these, or smaller.
I fuse all my transformers to close rated spec, if the very low value fuses are available.
Take the 100VA on a 240Vac supply. The close rated fuse would be 0.42A. I use a T500mA
Adding a 140r bank of resistors prevents that small fuse from blowing on repeated cold starts.
80VA and lower have a high resistance primary that is in effect a current limiter during start up.
I use an F500mA to fuse these, or smaller.
I have currently got my eye on this. https://www.ametherm.com/datasheets/ms2220005/
This one seems up to the caveman task.
This one seems up to the caveman task.
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Jeez, what monsters - these make the big Semicron's look small!
Curiously, I was just reading here about using some GaN transistors as diodes and seemingly getting excellent results - just saying, mind you
A few years ago, the guy that started the long-running 'Ultimate NOS 1541A dac' thread (E C DESIGNS) suggested in one of his power supply designs to use 2 diodes in // but one of them has an additional small series resistor thus allowing a 2 step charging pulse function - I was fascinated by the idea but never did try it - must get my finger out ....
I wonder what they use for charging current control at the 'Synchrotron Project' near the Monash Uni?
Curiously, I was just reading here about using some GaN transistors as diodes and seemingly getting excellent results - just saying, mind you
A few years ago, the guy that started the long-running 'Ultimate NOS 1541A dac' thread (E C DESIGNS) suggested in one of his power supply designs to use 2 diodes in // but one of them has an additional small series resistor thus allowing a 2 step charging pulse function - I was fascinated by the idea but never did try it - must get my finger out ....
I wonder what they use for charging current control at the 'Synchrotron Project' near the Monash Uni?
Thanks! Just curious to read the datasheet and try and work out why them in particular (noted on the screw terminals!).