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7. SPECIAL ADJUSTMENT FUNCTIONS
7.5 Low-pass filter
(1) Function
When a ball screw or the like is used, resona nce of high frequency may occur as the response level of the
servo system is increased. To prevent this, the low-pas s filter is factory-set to be valid for a torque
command. The filter frequency of this low-pass filter is automatically adjusted to the value in the following
expression.
Filter frequency(rad/s) 1 + GD2
VG2 10
When parameter No.PB23 is set to " 1 ", manual setting can be made with parameter No.PB18.
(2) Parameter
Set the operation of the low-pass filter se lection (parameter No.PB23.)
Parameter No.PB23
Low-pass filter selection
0: Automatic setting (initial value)
1: Manual setting (parameter No.PB18 setting)
7.6 Gain changing function
This function can change the gains. You can c hange between gains during rotation and gains during stop or
can use an input device to change gains durin g operation.
7.6.1 Applications
This function is used when.
(1) You want to increase the gains during servo lock but decrease the gains to reduce noise durin g 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 inpu t device to ensure stability of the servo system since the load
inertia moment ratio varies greatly during a s top (e.g. a large load is mounted on a carrier) .