Stepper motor sensors getting no power

I've successfully built my three stepper boards and when I run the motor check it seems fine. I have noticed though that as the board heats up I get a little glitchy action from the motor that goes away as I blow on the heat sink. Guess I'll need a fan.

Anyway, the problem I'm having is that two out of three of the boards is not supplying the needed 5v to my min/max sensor jacks. I seem to have checked everything but since the other tests say the board is fine I don't know what to do.

Has anyone else run into this, and if so, how did you fix it?

Check your powersupply first!

If you haven't any cold joints the 5V are simply passed from the powersupply directly to the pins.
(the leftmost cable of the powerjack)

It's a good idea to check C5 and C8 too maybe you short some circuit.

'sid

See layout:
[www.flickr.com]
(vcc is what you're looking for)

If the main 5V was the problem then the card wouldn't work at all.

And C5 and C8 on both boards are fine.

It's odd that it's affecting two boards at once.

I had problems with two of my stepperboards, too. The problem was that I set them to Slave - without connection the sync-lines.

So make sure all the Master/Slave jumpers are set to Master - and don't connect the sync-lines, you don't need them...

Ah-hah! That's exactly how I have my boards set!

It seemed the correct thing to do but I'll try your changes today and post back soon.

Thanks!

Try some thermal compound

[en.wikipedia.org]

It turns out my problem was more serious than mere jumper settings.

When I looked closely at the board I found that the circuit running between the C6 and POT that should supply voltage to the two sensor jacks had completely delaminated.

It is the exact same mistake on both boards which leads me to believe it is a manufacturing defect. I don't know why I didn't spot it sooner.

I've e-mailed Zach about it and hope he can help.

Wow! He's fast!

Got a message from Zach that he can send me the replacements.

Thanks Zach!