Err: short to gnd Warning: ph A,B disconnected on drv 0 1 5 6



  • ERROR: short to ground drivers 0 1 5 6. WARNING: phase A or B may be disconnected from drivers 0 1 5 6
    Hi guys, I'm trying to build my own printer:

    Duet 2 Wifi V1.03 + Duex5 V0.8a + Panel Due 7i.
    24V power supply
    6 nema 23 (4 Z axis, 2 for coreXY): Holding torque 1.61 Nm, Rated phase current 2.1 A, phase resistance 2.0 ohm, phase inductance 6.5 mH. I tried to give 1200mA to each motors.
    I'm trying to use drivers 2, 5 and 6 to control the 4 Z motors and 0 and 1 for XY. If I move only the driver 2 there's no problem, the 2 z motors move correctly and i tried the other motors on the same driver 2 and all it's fine, then i think there's no wrong wiring. The problem comes when i use M584 Z2:5:6 and when i try homing or when i try to home X (0) or Y (1). In all those cases the motors don't move and the Warning is a Phase A or B, disconnected from drivers 0, 1, 5 and 6 respectively. Another message is the Error: short to ground with the same drivers.
    I tried with 2.02a and 2.03beta1 firmware versions and there's the same problems.
    When the power is off with the M122 i see that all drivers are ok, S/G min max not available, when is on they are standstill, S/G min max not available. All the motors are disconnected from the mechanics then they don't have any load.
    I also connected the BlTouch to PMW3, a PT100 board with two sensors, two heater cartridges to E0 and E1 and two nema 17 to drivers 3 and 4 alimented with 800mA.
    0_1549805827246_config (1).g


  • administrators

    Have you paired the wires from each stepper motor into the 2 phases, and connected them correctly to the motor outputs on the Duet and DueX5?



  • @dc42 No, I understood a few minutes ago that the 2 phases are respectively 1A-1B and 2A-2B and I changed the order of the wires. I only noticed that the driver 6 was showing again the warning of a phase disconnected and the motor on it didn't move. Then I tried to use drivers 7 and 8 and all works fine. Could I had damage the driver 6 trying to home with wrong wires?
    thanks for the answer!


  • administrators

    Connecting the motors incorrectly sometimes damages the drivers. The current regulation can't work correctly when the phases are mixed up.



  • @dc42
    I thought I read somewhere those diode smoother boards could protect the drivers in such scenario, I wouldn't install and use one on this board, but if I remember is correctly, it would be a good Murphy detection device for initial setup.


  • administrators

    No the TL Smoothers don't protect the drivers.



  • Do you know of any kind of circuit that would protect the steppers? I would like to make something to protect the drivers since this could be a very easy goof up.


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