Mitsubishi Electric MELSEC-L LD75D, Руководство пользователя

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597
CHAPTER 12 CONTROL SUB FUNCTIONS
12
12.
7 O
ther
F
unct
ions
(b) S-curve acceleration/deceleration processing method
In this method, the motor burden is reduced during starting and stopping.
This is a method in which acceleration/deceleration is carried out gradually, based on the acceleration time,
deceleration time, speed limit value, and "[Pr.35] S-curve ratio" (1 to 100%) set by the user.
When the stepping motor is used, the acceleration around the inflection point on the s shape is faster
compared with the trapezoidal acceleration/deceleration. This may cause step-out.
*1
In this case, adjust the acceleration/deceleration time to decrease the acceleration around the inflection point,
or use a servo motor.
*1 When comparing the trapezoidal acceleration/deceleration and S-curve acceleration/deceleration processing method in
the same acceleration/deceleration time.
When a speed change request or override request is given during S-curve acceleration/deceleration
processing, S-curve acceleration/deceleration processing begins at the start of a speed change request or an
override request.
Set the required values for the "acceleration/deceleration method setting" in the parameters shown in the
following table, and write them to the LD75.
The set details are validated when written to the LD75.
Refer to

Page 118, Section 5.2 for the information on detail settings.
Remark
●
Parameters are set for each axis.
●
It is recommended that the parameters be set whenever possible with GX Works2. Execution by program uses many
programs and devices. The execution becomes complicated, and the scan times will increase.
Setting item Setting value Setting details Factory-set initial value
[Pr.34]
Acceleration/
deceleration process
selection

Set the acceleration/deceleration method.
0: Trapezoidal acceleration/deceleration processing
1: S-curve acceleration/deceleration processing
0
[Pr.35] S-curve ratio

Set the acceleration/deceleration curve when "1" is set in "[Pr.34]
Acceleration/deceleration processing selection".
100
Velocity
Time
When speed change
request is not given
Speed change (acceleration)
Command speed before speed change
Speed change request
Speed change (deceleration)