Originally Posted by rikkimantha The model is HOBBY CNC 4 AUPC Rev2 unipolar microstepping copyright 2005 |
Current Adjustment MOST IMPORTANT!
The stepper motor current MUST be adjusted before connecting any steppers to the driver board. Each axis can be adjusted to a different value. Current MUST be 500ma up to 3A per coil. With power applied to TB6 (12VDC min, 42VDC max) use a voltmeter with the black lead connected to TB6 terminal “minus” and the red lead touching the axis pad to the left of VR1, VR2, VR3, VR4. Clockwise movement increases the voltage, counter clockwise decreases the voltage. The following voltage MUST be set to achieve the correct amperage:
500ma = .103VDC
1A= .18VDC
1.5A= .27VDC
2A= .36VDC
2.5A= .45VDC
3A= .54VDC
For any amperage not shown use the following formula: desired amps times .18 equals Vref. Below .103VDC will disable the driver chip output. Keep Vref above .103V!