Re: 4 stage SISG

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: FIFTYGUY@xxxxxxx 

In a message dated 2/18/07 9:08:49 P.M. Eastern Standard Time, 
tesla@xxxxxxxxxx writes:

>I've priced suitable IGBTs.  "Sticker shock" is an understatement.

    Yeah, but Terry says they should last "forever" and have zero 
maintenance. Factor in near-silent operation, almost perfect 
efficiency, and the ability to "box up and forget about" the entire 
primary system, and I think it's definitely worth every penny.

    Of course, in the past three weeks I replaced two inverter 
drives at work that decided to blow up (7.5kW where the Semikron 
brick vaporized, the other a 15kW where a cheap *input rectifier* 
exploded on power-up). Telemecanique Alitvar 31 VFD's, if anybody's 
counting. No line or load reactors in the drives, and none with the 
OEM's installation (!). Only six months old... and these are mature 
industrial power electronics from a major manufacturer.

    To me, "solid state" means it's only solid until it becomes a 
conductive vapor. At least a few minutes with some emery cloth and a 
bit of fiddling is all it takes to get a SG back in working condition.

        I've got 10 of the IRGPS60B120KDP's on back-order from 
Digi-Key for a month now, so I'm in the same boat as you guys. Could 
somebody please tell I-R to start making more? Or are we gonna start 
having "roll-your-own IGBT" discussions? Will gluing a glass 
microscope slide and an extra layer on an SCR do the trick? ;)

-Phil LaBudde