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erratic stepper motor and pen servo

edited February 2016 in Egg-Bot
Wendall: Started having an erratic pen servo movement earlier today. When there is pen servo movement I also have slight pressure cogging of both stepper motors. When the pen servo stops jumping the stepper motors have very high pressure cogging to the point of not being able to move. At this point, the motors get extremely warm. This goes on as long as the egg bot is plugged in, flip flopping back and forth between the two states.  To this point I have re adjusted the motor voltage just to the point where the pen servo just stops ticking. This works for a couple minutes, and then restarts bouncing between the two states.    The power supply is the one that came with the unit, and I have tried usb3, and usb2 ports. Also running windows 10.
Inkscape is ver 0.48   Driver is 2.2.1 from 6/12/2011 and the Eibot board is Red. Any suggestions!


  • It sounds like you have multiple, unrelated issues. 

    The servo motor is likely broken and should be replaced. Unplug it from your EBB, and please contact our customer service directly about that:

    It sounds as though your motor current is set _way_ too high. The motors should not get warm, but not hot, and they should be able to be turned by hand, with some resistance. The motor current setting should not affect the servo, except that if you turn up the current enough, it could plausibly draw enough current to overload the power supply. 
  • Windell: Well I powered down the egg-bot last night. Powering it up this am, I have no control voltage to the steppers or the pen servo. No matter the location of the pot, min, midway max. Could all the erratic behavior yesterday been the pot or the ebb starting to fail? With failure this morning. The led for 3.3v is lite and usb connection are on and flashing normaly.  And the computer is seeing the egg-bot.

  • I'm not sure; it's possible that the pot has been damaged, or that your power supply has failed. We should take a look at it. Please contact customer service directly.
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