mdj wrote:
Michael J. Mahon wrote:I reached over, picked up the supply by the *open* ends, and had lifted the 10+ pound power supply about 4", so I had a firm grip on it. As I lifted, my fingers curled under the chassis just enough to contact the positive terminal of the filter capacitor. What happened in the next 10 milliseconds still amazes me! My arm and chest muscles were seized by a "higher power" and the heavy supply was instantly launched with toward the other side of the basement as if shot from a cannon! It hit the wall 25 feet away on the other side of the basement, transformer first, and fell to the concrete floor...:-) This is a fantastic story! Makes my audio amplifier power supplies seem tame (~90V secondaries with 40,000uF)
That's a lot of stored energy--162 Joules! You could do some serious spot welding with that! And 90v is enough to shock humans (while anything under 45v is not).
I have a bit of a wierd fascination with power supplies, which I guess is kind of like the oily hand brigades fascination with cubic inches. You mentioned a while back some experience with an ECL machine - while fairly harmless, I'm sure the power supply for such system would be really a sight to behold (at least those of us who are fascinated by banks of capacitors) :-)
True. A large ECL machine demands low voltage at very high current. The prototype I mentioned had a couple of 500A power supplies at 3.7v (or something like that). They were high frequency switching supplies, but since the current was so high the filter capacitors were also huge-- like 100,000uF (or .1F ;-). The power supplies were about 20% of the volume of the machine. I was really impressed by the bus bars that delivered the power--about 1" x 3/8"! -michael New, faster SUDOKU v2.0 solver for Apple II's! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it's seriously underused."