Re: L298 goes boom ( It's Fixed!- Yeah! )

Hey guys,
well the day is almost over and I finally got my mill working! well,
3 out of the 4 axis :) I got the stuff from mouser today and quickly
went to work. I put in the L298 and L297 into all axis and started
checking the voltage switch and stuff on the camtronic board. As I
was checking pin 1 on the L298, I slipped and the lead from the VOM
touched pin 3 also. A little "Tick and a spark" and it was history
for the Z axis L298 :( I did a quick check by plugging in the stepper
(No Power) and it was very gritty :(

I then de-soldered the L298 from the single 4th axis, man what a
project. Put that into the Z axis and checked everything. Held my
breath and plugged it in, and a little "zap" at that L298 or so it
seemed! O man! I quickly unplugged it and plugged in the stepper to
see if it was gritty but to my surprise it wasn't...a good sign.

I thought, I wondered and I asked what I got myself into :) I plugged
it in again (not knowing what to check) and nothing worked other then
the fan and the power and check LED did not come on!! After some
thinking I found the 7812 burned out. Back to radio shack, and I got
a new 7812 and 7805 plus 2 of there beefier heatsinks to add to mine
homemade ones. Put everything back togeher and to make this very long
story short...IT WORKS!!!!!

Since I only bought 4 L298, I have just removed the 4th axis as I
really don't use it. I don't think having 4 drivers is of any use to
a hobbiest as we don't have/ can't afford 4D converting programs, as
I learn more.

I plan to get another single unit from Dan, get one L298 from him to
fix the "4th axis" and use those 2 on the lathe. Not much for cnc but
more so I don't have to crank the handles so much :)

It's still working, keep your fingers crossed!

thanks for the help everyone
tauseef