3 axis driver...Fuses keep blowing

[dudz]

I have these drivers ; www.easy-cnc.com * Your best option in driver boards for CNC machines

I have used it dozens of times without problems. Now the X and Y axis fuses keep blowing as soon as the PSU is switched on. I have tried disconnecting the pc input and motor outputs and then switching on power. The same two fuses blow instantly. I can find no connection problems. I am assuming two of the optocouplers or IC drivers has burnt out (which can be replaced) although I do not know where to buy replacements.

[Web Goblin]

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.

[dudz]

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.

[dudz]

Then here is Ebay.... (I think they are the same spec ? )
NEW Allegro A3977 STEPPING STEPPER MOTOR DRIVER | eBay

[Web Goblin]

Look like thats the problem then if the fuses are intact. The only real way to prove it though is by getting some new ones and plugging them in. Both ICs you have linked to look the same so take your pick of what you want. RS might be a bit more expensive but you should get them a lot quicker. You might want to get a few spares as well.

[dudz]

Look like thats the problem then if the fuses are intact. The only real way to prove it though is by getting some new ones and plugging them in. Both ICs you have linked to look the same so take your pick of what you want. RS might be a bit more expensive but you should get them a lot quicker. You might want to get a few spares as well.

I pulled the Z axis IC and put it in the X axis slot, powered up, and no blown fuses. So great. I have bought 4 from Ebay as RS wont ship to France, and the RS in France is Twice the price plus tax plus delivery.