User`s manual

5-37

Functions

5. Functions

(2) Procedure for setting the gain change function

1. Set the "Gain change mode" (Fd-30) to "AUto".

• Set the "Position error width for gain change" (Fd-31).

• The position control gain is changed based on the interrelation of "Position error

monitor" (d-09) and "Position error width for gain change" (Fd-31).

2. Set the "Second position control cut-off frequency" (Fd-32) and the "Second speed

control cut-off frequency" (Fd-34).

Default values are:

• The default value for the "Second position control cut-off frequency" (Fd-32) is

double the value (10.00 [Hz]) of the "Position control cut-off frequency" (Fd-09).

• The default value for the "Second speed control cut-off frequency" (Fd-34) is

double the value (60.00 [Hz]) of the "Speed control cut-off frequency" (Fd-01).

• As a general guide set the Fd-32 to 1/6th or less of Fd-34.

3. After making the settings in 1 and 2 above, turn the servo on.

Note 1: A large gain difference during the gain change might cause mechanical shocks

to the machine. If that happens, set the

"Position gain change time constant"

(Fd-33) and "Speed gain change time constant" (Fd-35) to a large value (the

default value is set to 1 [ms]).

Note 2: If abnormal noise and oscillation occur during servo-lock, then set the

"Second position control cut-off frequency" (Fd-32) and the "Second speed

control cut-off frequency" (Fd-34) to a value low enough so that abnormal

noise and oscillation do not occur.