Two semi random thoughts catalysed by various comments.

(1) If you use a boost / up convertyer somewhere in the chain then failiure
to operate cannot apply excess voltage.
If any one of two or more systems can this converter down using fully
independent shut down circuitry it could be designed to be very hard indeed
for it to produce excess voltage.

(2) For custom inductors I recommend that you at least glance through what
"Micrometals" offer. As well as some useful inductance value design tools
for various topologies they have design software that allows inductor
longevity in a given application to be calculated. High power cores are
usually metal powder based using binders in the core. Core losses produce
temperature reise which degrades the binder. Failure finally occurs in an
interesting thermal runaway mode where losses increase causing more
temperature causing more ... .

Micrometal have trademarked core markings. Their products are well enough
regarded that they are copied as far as colour goes but not, it seems , as
far as binder quality goes. Be sure you are using genuine product. Initial
inductance characteristics may be essentially identical but ... .

________________

Lonnng ago I specd a micrometal core in a converter in a power supply in an
exercise machine built in Taiwan - user drives alternator with wide range
of Vout and system is powered by down converter. I made it VERY clear that
use of genuine Micrometal product was essential. However ... :-).


       Russell
--=20
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