From: Winfield Hill
Subject: Re: High DC current Transfer Switch
Date: 30 Nov 2002 18:41:27 -0800
Organization: Rowland Institute
References: <email@example.com> <3DE64488.D6CE9A83@mfi.net> <firstname.lastname@example.org>
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John Fields wrote...
> Winfield Hill wrote:
>> I'm not sure. On one hand, the 600A contactor I used in a recent
>> design was rather large, about 4 to 6-inches on a side IIRC. On
>> the other hand, my 300V 6000A solid-state transfer switch used six
>> large-sized hockey-puck TRIACs with Wakefield high-pressure-spring
>> heat-sink clamps, and it wasn't _that_ large or impressive. While
>> my 6000A pulse setup might not meet our O.P.'s continuous-operation
>> requirement, neither did it use the largest devices available from
>> Powerex, so it's likely a solid-state solution could serve well.
>> You know, the stuff that modern locomotive-engine designers use.
> You're not sure? Your 6kA < 100% duty cycle stuff might not meet
> the OP's 10kA continuous requirements?
> C'mon, Win, we look to you for guidance... Clue us in on how many
> of those Powerex FETS(?) it would take to do the job, OK?
Those were thyristors, not FETs. I'm on vacation away from my files,
so you'll have to look it up yourself. :>) But I did find a 3100A
unit on the web, http://www.pwrx.com/pwrx/docs/fgc6000ax-120ds.pdf
I'm sure serious power engineers develop a relationship with the
factory and thereby get access to the really good stuff.
> Also, how about what it takes to keep them from committing suicide
> when they turn off and the size of the fan or fridge (H2O/LN2
> heatsink) needed to keep them cool while they're on CW ;^)
Nah, mine used water cooling, with cool-looking automotive-style
adjustable-force leaf springs, complete with individual force-
readout gauges to insure proper thermal and electrical contact,
And appropriate snubbers are required, of course.