
B–65160E/02
2. FUNCTION EXPLANATION
FANUC AC SPINDLE MOTOR a series
113
Velocity loop proportion gain in Cs contouring control (LOW gear)
CTH1A=1
6547 3047 3047 4047
Standard setting : 30
These parameters specify the proportional gains of the velocity loop in Cs
contouring control mode.
A parameter is selected by the CTH1A input signal.
Increasing these parameters and the velocity loop integral gain parameters
(No. 4054 and up) improves rigidity in Cs contour cutting.
Note that, however, setting too large a value for these parameters will
produce oscillation.
The range of values that can be specified varies with the machine system.
Guidelines for setting these parameters are given below.
Generally, the larger the motor, the larger the value that can be specified.
In machines where belts or gears are used as the drive mechanism, belt
spring elements or gear backlash, sometimes prevent large values from
being specified.
Velocity loop proportional gain = 10 to 50
Velocity loop integral gain = 50 to 500
16i/1601515i
Velocity loop integral gain in Cs contouring control (HIGH gear)
CTH1A=0
6554 3054 3054 4054
Velocity loop integral gain in Cs contouring control (LOW gear)
CTH1A=1
6555 3055 3055 4055
Data unit :
Data range : 0 to 32767
Standard setting : 50
These parameters specify the integral gains of the velocity loop for Cs
contouring control mode.
A parameter is selected by the CTH1A input signal.
Increasing these parameters and the velocity loop proportional gain
parameters (No. 4046 and up) improves rigidity in Cs contour cutting.
16i/1601515i
Gear ratio (HIGH) CTH1A=0, CTH2A=0
6556 3056 3056 4056
Gear ratio (MEDIUM HIGH) CTH1A=0, CTH2A=1
6557 3057 3057 4057
Gear ratio (MEDIUM LOW) CTH1A=1, CTH2A=0
6558 3058 3058 4058
Gear ratio (LOW) CTH1A=1, CTH2A=1
6559 3059 3059 4059
Data unit : Motor rotation for one rotation of spindle 100
(When parameter No. 4006 #1 (GRUNIT) is 1,
motor rotation 100)
Data range : 0 to 32767
Standard setting : 100
These parameters set the gear ratio of the spindle motor to the spindle.