Losing steps/position, again

[dazp1976]

JAZZ - yes the 5v to the BOB is fed from the vertcal 42 pin connector on the Baldor card. I think I would prefer to by a 5v transformer which should then make the Baldor redundant, just have to work out how to do the E-Stop.

I have found the BOB axis controls, they also feed into the 42 pin connector and am looking for the feeds from the board to the steppers (4 found and 2 to go)

These boards are usually wired as this below. Trace the wiring back just to double check it to be sure.

Shows 5v in on the bottom 3 right connectors. This is likely how it's powered atm.
e-stop P10, limits P12-15, spindle switch+speed all run off the seperate 24v input on the right.

Was at least 5 years ago when I was advised against using the bottom connectors for 5v. Told it's more ideal to modify a usb lead instead due to the protection circuitry.
Trying to re-find information on the net is a pig.

[JAZZCNC]

Was at least 5 years ago when I was advised against using the bottom connectors for 5v. Told it's more ideal to modify a usb lead instead due to the protection circuitry.
Trying to re-find information on the net is a pig.

Not sure I'd trust that information. I wouldn't trust USB for a CNC machine, not even to provide 5V as it's notorious for dropping out. The PSU would be protected by it's own circuitry and if the BOB as protection built into the USB connection which isn't on the 5v terminal then I'd take the risk for the sake of £5. I'd rather have it blow up than keep cutting out thru power dropouts while cutting, Only takes one job and you've lost far more than £5.

[dazp1976]

Not sure I'd trust that information. I wouldn't trust USB for a CNC machine, not even to provide 5V as it's notorious for dropping out. The PSU would be protected by it's own circuitry and if the BOB as protection built into the USB connection which isn't on the 5v terminal then I'd take the risk for the sake of £5. I'd rather have it blow up than keep cutting out thru power dropouts while cutting, Only takes one job and you've lost far more than £5.

It's worked so far taking 5v from a small switched psu into a usb cable. However. I might change it round now you've convinced me on it.
If I can make enough money I'll be swapping to an ess and get a new BoB rated for 200+khz asap for axis control anyway. My current board will go to run spindle/ limits/ estop etc. Well that's once I pluck up the courage to tackle the spindle wiring