Adjusting The Motor Offset - GRAPHTEC CUTTING PRO FC3100-60 Service Manual

5.7 Adjusting the Motor Offset

Note : Before adjusting the motor driver IC's offset, disconnect the encoder lines of the X and Y motors
from the main board's P22 and P32 connectors.
Caution : Be sure to adjust only one motor at a time. Before you begin, loosen and remove the X or Y
synchronous belt.
(1) Set the SW1 DIP switch as shown below and then turn on the plotter.
* Set only Bit 8 to OFF
(2) Test pins TP11 to TP15 of the test pin connector jig correspond to Pins 1 to 5 of the P100 connector.
(3) Connect the probe of an oscilloscope to TP11 and connect either TP10 or TP15 to ground level. The
wave-form shown in Fig. 1 appears at the oscilloscope.
(4) Turn the VR2 (X-OFFSET) trimmer until the wave-form peaks are the same height as shown in Fig.
2.
(5) To adjust the Y motor offset, repeat Steps (2) to (4) with the following changes.
Test pin : TP12 (connect TP10 or TP15 to ground level)
Trimmer : VR1 (Y-OFFSET)
(6) When adjustments are completed, return the DIP switch to its default settings and then turn off the
plotter. Also reconnect the X and Y motor encoder lines and remount the X and Y synchronous belts.
Fig. 1
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FC3100-60 Service Manual
P/N53802-031T Rev. A
Vertical axis : 1 V/division
Horizontal axis : 5 us/division
Fig. 2