No Voltage From Stepper Drivers



  • Just recently purchased a Duet 2 wifi, went through the guides and set everything up. Upon completion everything worked barring the drives themselves. My bed heater, extruder heater, all thermocouples, and all end stops function correctly. I am using the M564 S0 H0 command in order to move the motors without homing, however when the command is sent to move any of the motors nothing happens and no error is sent through the console.

    Diagnosis went as follows:

    • Verified polarity and phases of stepper motors

    • Reversed direction of stepper motors in config.g

    • Verified all stepper motors are functional using an Arduino and external driver

    • Verified integrity of all crimps and connections

    • Measured voltage at pins directly on the Duet Wi-Fi using a voltmeter, no voltage coming from pins when command is sent

    • Verified all motor parameters are defined in config.g barring jerk

    • Updated firmware to absolute latest

    • Stepper motor drivers show no obvious pits or burn marks

    I am assuming this issue must lie on the software end of things unless my board showed up with 5 bad motor drivers. I cannot think of anything I have done that would have damaged the board, and said damage would have to be incredibly specific in order to just damage all the driver chips and leave everything else intact. As I mentioned earlier, all other functions work and I was able to tune the heaters and configure the endstops without issue. The web interface shows the "predicted" position of the gantries but there is no movement from the motors or voltage off the drivers.

    Machine is a basic cartesian printer with low endstops for X and Z axis, high endstop for Y axis. Tronxy brand chinese motors, all motors worked excellent with previous controller. I have double checked the phase of all motors and tested them using another driver board. Power supply is 12v 20amp, drivers do not output even with no other loads (bed heater and extruder heat off).

    Attached is my config.g, please note that the direction of all my steppers is reversed due to the troubleshooting process mentioned above. I am clearly missing something in the config.g and I would appreciate any help that I can get. Thank you in advance.

    Config file: 0_1540436625895_config.g



  • Hi,

    What command are you sending to test the steppers?

    Frederick


  • administrators

    1. Please test the stepper motors by sending these commands:

    G91
    G1 S2 X10
    G1 S2 Y10
    G1 S2 Z10

    Each of the g1 commands should move the motor 10mm in the + direction of the axis concerned.

    1. Can you confirm that you have VIN power applied, and that at least one of the heaters in your printer is working i.e. you can heat it up?

    2. Please confirm that you have nothing connected to the expansion connector.

    3. Please send M906 with no parameters and verify the the stepper motors currents reported are the ones you set in the M906 command in config.g. Also send M913 and verify that all currents are reported as 100%.



  • @dc42 said in No Voltage From Stepper Drivers:

    1. Please test the stepper motors by sending these commands:

    G91
    G1 S2 X10
    G1 S2 Y10
    G1 S2 Z10

    Each of the g1 commands should move the motor 10mm in the + direction of the axis concerned.

    This was done in the original trouble shooting steps. I repeated this and the result was the same, the predicted position increased as expected but there is no movement from any of the motors. Measuring the pins on the board with an (admittedly slow) voltmeter shows no voltage, bar graph does not jump. This is repeatable for all axis and extruder.

    1. Can you confirm that you have VIN power applied, and that at least one of the heaters in your printer is working i.e. you can heat it up?

    As mentioned in the original post VIN power is correctly applied. Both the extruder and bed heater work. All endstops are functional. LED's are lit on board and turn on correctly when endstops are closed. VIN power direction was double checked. Leads were removed, new crimps were applied, and were fastened back into screw terminals. Just to verify, I double checked voltage at the VIN connector and found 9.67 volts. Found power supply switched to 220 VAC input DOH! Switched power supply to 110 VAC input and the issue was resolved.

    Thanks for your help! Figured I was overlooking something obvious, did not realise it was that obvious. Shows the importance of starting at the beginning.


  • administrators

    @stirfrybeans glad you got it sorted, thanks for confirming what the issue was!


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