RE: Components from ebay

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com> 

 >I saw few IGBTs on ebay. The description said that those were removed from
 >working equipment
 >and are UNTESTED. Are those components reliable ? Will they really work ?

I have two Powerex CM600HA-24H 600A 1.2kV IGBT blocks that were sold on eBay
as "Removed from working equipment and untested". One was most definitely
used- the casing was cracked. But they work fine and I've managed to make
5ft sparks with them so far.

However, that doesn't mean that every IGBT on eBay will work :P

If you're spending money, don't just buy any old IGBTs... First check to
make sure they're not too slow for your application. IGBTs have got much
faster and more tolerant of hard switching in the last few years. I think it
is possible to build a SSTC with old-style slow IGBTs (as long as you use a
big lowish frequency resonator, a series resonant primary, and an
interrupter, a la DRSSTC) but it's a difficult job.

The new high-speed IGBTs make it a lot easier, they seem to happily drive an
untuned primary at several hundred kHz, and are more tolerant of mistuning.
Alas it's not so easy to pick them up for cheap :(

Steve C.