The power plug provided will be connected at
J3
on the printed circuit board. The center is
+VDC and the outside barrel of the plug is 0 VDC common (DC ground). The positive wire is
identified with a white-stripe running the full length of the wire. The solid black wire should be
connected to ground. The power supply can be anywhere in the range of 7-28 volts DC. Find a
suitable power source in the cabinet and connect the flying lead connections to a power source.
Test the voltage and polarity before plugging into the USBCNC board. Use the CNCs DC
common (0 VDC) on the pin 7 on the machines DB25 RS232 plug, this is typical, but please
verify in the machines wiring manual. Note if you are unsure where to tap the DC voltage inside
the CNC, purchase the optional DIN rail power supply from Calmotion. This optional power
supply uses 120 to 240VAC line voltage to created the DC voltage for the USBCNC.
Apply power to the unit. A green LED should illuminate on the controller indicating that power
has been applied. If properly connected, the keypad will also illuminate after a slight delay.
To Adjust the Display Contrast
An orange potentiometer (
R2
) located on the back of the display board can be used to adjust the
contrast of the keypad display. This potentiometer should be accessible through the large
diameter hole in the control box. (Note: the R20 on the USBCNC control board does
not
adjust
the contrast).
