Jim wrote:

> Considerably reducing DC-DC converter output filter
> capacitance and/or load current can almost always solve
> the problem of erratic power supply startup related to
> high source resistance,

When I checked the data sheet for the IP1215S isolating
DC-DC converter I spotted that it said max 47uF load
capacitance - and I had 100uF hanging on each rail.

Hopefully that's the answer.  For some reason I can't
reproduce the start-up problem in the office even though
I've got slightly higher cable resistance.

I like these XP power IP series converters, good isolation
and they have a large input voltage range.

--
Paul Nicholson
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