[Amps] Results from new PSUD... resistor b4 the B+ filter caps !

[Paul Christensen]

> It seems to me that a primary step start is a much better way to go, if 
> one
> is even needed. As long as the breaker don't trip and the diodes can 
> handle
> the peak current.

But the series R between the rectifier and filter C should still keep 
current limited in the event of a filter C short -- and hopefully, assist in 
protecting the rectifier stack.  That's something the step-start circuit 
cannot protect after the initial "step" sequence.

My "take away" from this discussion is that a distributed surge suppression 
approach may be best comprising of: 1) primary step-start to strictly limit 
filter C in-rush current, 2) series R between the rectifier and filter C for 
rectifier preservation during a C short; and 3) Series R close to the anode 
for arc-fault protection of all HV cabling, inter-compartment HV connectors 
and components ahead of the anode.

Regarding placement of series R between the rectifier and filter C on a gg 
amplifier with a traditional elevated HV(-) return, I am still pondering 
whether that R should be broken up in equal amounts of say 10-ohms each 
between both HV terminals and the filter C.  In other words, is there some 
fault condition where a surge resistor placed in the HV(-) lead between the 
rectifier and filter C that would assist in fault protection?

Paul, W9AC