Quote Originally Posted by Web Goblin View Post
Try RS Components. Have you tried unplugging the optos to see if that still blows the fuses? There is also a transistor or voltage regulator standing up just behind the fuse. Whats the part number on it? This could be faulty as well.
I took the two stepper motor driver chips out (x and Y). Put new fuses in... now all 3 power LED's come on and the fuses don't blow. Chip number A3977SEDT A 1201 917M

I checked RS ....
Buy Motor Driver ICs Stepper Motor Driver, Dual Full PLCC44 Allegro Microsystems A3977SEDTR-T online from RS for next day delivery.