4KW Cherokee International SMPS.

[carampman]

I bought this on Ebay a while back and am just now getting around to messing with it. It is rated at 27 volts, 148 amps. It has two three inch diameter toroids stacked together and a PFC front end. The control chip is a UC3895. I am hoping to reverse engineer it enough to change the output voltage to about 14. It was designed as a hot-swap supply and will not run stand alone as it sits. I am getting in it to try and bypass the interface circuits so it will run stand-alone.

I will get some pictures up soon.

 

[MicrosiM]

I bought this on Ebay a while back and am just now getting around to messing with it. It is rated at 27 volts, 148 amps. It has two three inch diameter toroids stacked together and a PFC front end. The control chip is a UC3895. I am hoping to reverse engineer it enough to change the output voltage to about 14. It was designed as a hot-swap supply and will not run stand alone as it sits. I am getting in it to try and bypass the interface circuits so it will run stand-alone.

I will get some pictures up soon.

Will be waiting some pictures, Looks very interesting

 

[m0gjr]

how many turns on the toroids

 

[carampman]

I have not taken it far enough apart yet to count windings, they are multi-filar so it is almost impossible to count without unwinding the cores. I spoke with GE who took over Cherokee in the states and they refused to give me ANY info on it. I hate corporations like that.

The control is done by a phase shifted pwm I believe it is a UC 3895. This was a custom made supply and is hot-swappable so I am needing to figure out how to get it to turn on. I think it used an external control that fed back and controlled output voltage. It will not turn on just by providing input power.

I have a TON of stuff going on right now with the Maker Faire coming up June 24th-26th. It takes priority over hacking power supplies. I will try and get more info/pictures up soon.


Steve

 

[Yosemite]

some pictures may help us think better how we can provide some help!

 

[carampman]

Hi all, sorry I have been gone for quite a while. Work and some personal stuff have kept me tied up. I did talk to the people at GE (who now own Cherokee in the states) and they refused to give me any help or info. (Bastards!) Figures from the company that screwed Tesla. Anyway, enough of my rant. I am going to be getting back to this project shortly and will post the pics and progress.