Mach3 Help required

Years ago I bought and assembled a HobbyCNC pcb kit, but the maximum current is 3Amp which is a bit limiting.

Recently ran it using Mach3 with my Warp9 ethernet SmoothStepper - no problem - works fine on X,Y & Z.

I have a single 4.2Amp Bi-polar stepper wired up via a Break out board and SmoothStepper to the X output of a DM542 Stepper Driver ...... nothing!!

I have double checked the Mach3 settings to no avail. Slave the SmoothStepper back to the HobbyCNC - perfect.

Now I am at a complete loss. I imagine it's only going to be a selection or two incorrect with Mach3 but no idea now and looking for some help/direction please if possible. Have followed the Mach3 manual settings to the letter.

To trial the set up I have the Stepper Driver etc on a separate board (X axis only) - it's stand alone and the wiring layout is clear and easily checked, not a rats nest!

Voltages:- 5.1v input to SmoothStepper, 5.08v input to Break Out Board & 37v to driver (20Amp Supply)
See photos for layout details

I'd be very grateful for any input at all.

Kind regards,

Barry

Ok Well if you are using any of the inputs to the BOB you have to connect 12-24V to the other power connections near the blue relay (I think the middle two in the green strip) It probably says on the back of the pcb.

Otherwise the bob won't work

Quote:

---

Originally Posted by Clive S

Ok Well if you are using any of the inputs to the BOB you have to connect 12-24V to the other power connections near the blue relay (I think the middle two in the green strip) It probably says on the back of the pcb.

Otherwise the bob won't work

---

Here is a link to the manual for the BoB https://www.dropbox.com/s/gfq4isvihn...rd-EN.pdf?dl=0 The USB connected 5v only supplies the input optos. You also need 5v to power the optos on the output side, this (I believe) is derived from the 12-24V input, which also needs a ground connection. I use this board and have had no problems using a common ground from a 5/12V power supply and ignoring the PC derived 5v.

Actually, I believe it's the inputs that require the 12V-24V. The outputs should work with just the USB cable connected. At least that's how the one I have worked.

Quote:

---

Originally Posted by Ger21

Actually, I believe it's the inputs that require the 12V-24V. The outputs should work with just the USB cable connected. At least that's how the one I have worked.

---

That doesn't quite make sense Gerry! The inputs are connected to the computer and require 5v/gnd to drive the buffer circuit. If the optocouplers have no buffering then the 5v is unnecessary as the LED in the opto is driven directly from the signals and ground connections in the D25 cable. You will then need 5v to bias the photo transistor in the output stage, which should be derived from a power source other than the computer 5v in order to give the galvanic separation.
The USB socket on this board connects through to two terminals labelled PC 5v and PC GND and these I just connect to the power supply 5v/GND - it works.

I probably have a spare one of these boards and if I find it I will have a poke round it with a meter.

I may not be 100% correct, but it ain't worth a dick slapping contest.

For the sake of clarity for the op (Barry) the board need 5v and 12-24V with the grounds connected together to the BOB in order for the inputs and outputs to work. The USB is better not being used.

Added 15v power to the relay side of the board as suggested. That's put the green LED in the corner diagonally opposite the relay ON.

RESET switch is flashing and on the diagnostic screen the M1++ and M1-- reds are illuminated. Impossible to RESET so limit wire link removed, RESET stops flashing but still no output to the stepper motor.

Should have pointed out I'm not using the 5v USB supply from the PC this is wired up to a separate regulated 5v PSU.