Mitsubishi Electric MELSERVO-JN Series, Instruction Manual

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7 - 13
7. SPECIAL ADJUSTMENT FUNCTIONS
7.2.5 Low-pass filter
(1) Function
When a ballscrew or the like is used, resonance of high frequency may occur as the response level of the
servo system is increased. To prevent this, the low-pass filter for a torque command is set valid. In the initial
setting, the filter frequency of the low-pass filter is automatically adjusted to the value in the following
expression.
Filter frequency(rad/s)
1 + GD2
VG2
10
However, when an automatically adjusted value is smaller than VG2, the filter frequency will be the VG2
value.
When parameter No. PB23 is set to " 1 ", manual setting can be made by parameter No. PB18.
(2) Parameter
Set the low-pass filter selection (parameter No. PB23.)
Low-pass filter selection
0: Automatic setting (initial value)
1: Manual setting (parameter No. PB18 setting)
Parameter No. PB23
0 0
7.3 Gain changing function
POINT
The functions given in this section are not generally required to use. Use these
functions when the machine status is not satisfactory after making adjustment in
the methods given in chapter 6.
This function can change the gains. Gains can be changed using an input device or gain switching conditions
(servo motor speed, etc.)
7.3.1 Applications
This function is used when:
(1) You want to increase the gains during servo lock but decrease the gains to reduce noise during rotation.
(2) You want to increase the gains during settling to shorten the stop settling time.
(3) You want to change the gains using an input device to ensure stability of the servo system since the load to
motor inertia moment ratio varies greatly during a stop (e.g. a large load is mounted on a carrier).