3
DC Amplifier Adjustment Procedure
Machine with Scales:
Before adjusting the amplifier, verify that scale cable (if applicable) is disconnected
from the 1010 axis card of the corresponding axis amplifier to be adjusted. If it is
connected (using the glass scale feedback), power down the machine, disconnect
the cable, and then power up the machine. See parameter note for Rotary Scale at
the page of these instructions.
The scale feedback is the upper blue, edge connector; the bottom connector is for
the motor encoder feedback (do not remove).
After the amplifier is adjusted you’ll need to power down the machine and install the
scale connector.
Adjusting the amplifier:
1) Turn the
Loop Gain
potentiometer all the way clockwise.
2) Turn the
Current Limit
potentiometer all the way clockwise. Full current is set
by turning the pot fully clockwise. For the large DC motors (6000 series) the
pot is set fully clockwise. For smaller motors (4000 series) the value can be
reduced after final adjustments. Not enough current will cause the machine to
fault during a rapid move and display the message “MOTOR OVERLOAD”.
3) Slowly turn the
Compensation
potentiometer counter clockwise until the axis motor
produces a High frequency vibration (Buzz), then turn the potentiometer clockwise until it
stops buzzing and add one more full turn clockwise from that point.
4) Begin cycling the machine to adjust the
Signal Gain and Balance
potentiometers.
Enter the following program if adjusting an X, Y or Z axis:
N1 M91 M49 G91 F150.
N2 G1 X-3.Y-3.Z-3.
N3 X3.Y3.Z3.
N4 M99 P2
Enter the following program if adjusting a Rotary axis amplifier:
First select the Feedrate using the ratio table on the last page and use it in line 2 of the
program below for the F*** value.
N1 M91 M49 G91
N2 A-90. G1 F***
N3 A90.
N4 M99 P2
5) Press AUTO, to start the program running.
6) Turn the
Signal Gain
potentiometer until the CNC display of the axis to be adjusted
reads the correct following error count while running the program.
Clockwise will reduce the following error and counterclockwise will increase the value.
The following error is the number displayed to the right of the position display value.
Publication No. D-9812-BRUSH AMP v1.5
February 2012
