Maybe this will save someone problems in the future for the dd8727t3v1 triple bipolar stepping motor driver. I have finally solved the failing issues of why these triple drivers fail. I was loosing steps badly and could not solve why and why I was having really bad vibrations. The poorly translated manuals say to power the driver to measure the current so the current can be adjusted and set for the stepper motor. Well I have had multi motors drivers fail on me. And at this point I caught it happen, and HOW it happens. If the current POT is touched while the driver is powered, it instantly blows the logic controller in the microstepping controller. My belief is that the logic controller reads the POT on start up and locks in its current control freq. But if it is adjusted when powered its un-able to handle the change and burns up. The result is a driver that goes from micro stepping nicely to micro stepping poorly to more or less whole stepping one of the 4 bipolar phases. I discovered this by adjusting the pot by accident in frustration do to having multi failed drives in the same day. Not understanding as to why it just happened. The last one to fail on me, the second I touched the pot the motor was in motion and I heard it go from smooth to failing micro step sounds just like the others. Now the others were out of the blue " " because the machine was not moving. In Fact I made adjustments and was just leaving the machine idling checking on the TEMP of the stepper motors.

So in short dd8727t3v1 and likely like models of stepper drivers. do NOT adjust anything, or settings on these drivers including current IF it is powered. Anything that is changed when its powered will blow the driver even though the manual describes doing it.