Omron R88M-K - 7-8 Soft Start

7 Applied Functions
7-26
G5-series AC Servomotors and Servo Drives User’s Manual (with Built-in EtherCAT Communications)
7-8 Soft Start
This function is used to control the rotation speed. It sets the acceleration and deceleration against the
rotation speed command in the Servo Drive.
The function can be used for step rotation speed commands, and allows soft starts. The S-curve
Acceleration and Deceleration function is used to reduce any impacts by acceleration changes.
Set the time required for a step speed command to reach the maximum motor rotation speed into the
Soft Start Acceleration Time (3312 hex). In the same manner, set the time required for the command to
decrease the speed from the maximum motor rotation speed to 0 r/min into the Soft Start Deceleration
Time (3313 hex).
The time taken for acceleration or deceleration is calculated by the following formula, where Vc [r/min] is
the target rotation speed of the speed command.
Precautions for Correct UsePrecautions for Correct Use
• Do not set the Soft Start Acceleration Time and the Soft Start Deceleration Time when the
position loop structure with a Host Controller is used.
7-8-1 Objects Requiring Settings
Index Name Description Reference
3312 hex Soft Start Acceleration Time Sets the acceleration time for the rotation speed
command input.
page 9-26
3313 hex Soft Start Deceleration Time Sets the deceleration time for the rotation speed
command input.
page 9-26
3314 hex S-curve Acceleration/
Deceleration Time Setting
Sets the acceleration or deceleration processing
S-curve time for the rotation speed command input.
page 9-27
7-8-2 Soft Start Acceleration or Deceleration Time
A
cceleration Time [ms] = Vc
/
Maximum motor rotation speed × 3312 hex × 1 ms
Deceleration Time
[
ms
]
= Vc / Maximum motor rotation s
p
eed × 3313 hex × 1 ms
Rotation speed [r
/
min]
Maximum motor
rotation speed
Step input of a rotation
speed
command
Rotation speed
command after
acceleration or
deceleration
processing
33
12 hex × 1ms
33
1
3
hex × 1ms