OLTC - Inside the PWRX CM600HA-24H

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

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

Hi All,

I got a batch of those 600 amp 1200V PowerX CM600HA-24H IGBTs that Steve C. 
uses on his wonderful OLTC.  Mine were a little more "used" since a few had 
red tech grease pencil "X"'s one them...  Hey!  I know what that means 
:D  They did the preventive maintenance of replacing the IGBTs a few 
milliseconds too late...

No problem since I got them at 1% the retail price ;-))

It read "gate ****** up" on the meter.  So I pulled the screws and applied 
a "spread spectrum force instrument" to the case (hammer).  I then chopped 
the buss bars and dug through the "gorilla snot" as is typical for those 
familiar with the high art of de-kitting large brick power devices...  So, 
as if Hot-streamer was not bogged down tonight with all 1500 of you 
downloading the cap x-ray pics :o))), here is what is inside:

http://hot-streamer-dot-com/temp/CM600HA-24H.jpg

Just eight big ~ 20mm IGBT die in parallel and the eight reverse diodes on 
a aluminum nitride substrate.  The gates on two have been over voltage and 
fried two chips.  Probably another device incinerated and the buss voltage 
got onto the gate buss.

Sort of neat.  Be sure not the flex the copper bottom too much ;-))

Cheers,

	Terry