Yaskawa Sigma II Series DC Power Input SGMAJ - Manual (Page 215)

8 Operation
8.5.4 Soft Start
8-42
8.5.4 Soft Start
The soft start function converts the stepwise speed reference inside the SERVOPACK to a consistent rate of
acceleration and deceleration.
8.5.5 Speed Reference Filter
8.5.6 Using the Zero Clamp Function
(1) Zero Clamp Function
The zero clamp function is used for systems where the host controller does not form a position loop for the speed
reference input. When the zero clamp signal (/ZCLAMP) is ON, a position loop is formed inside the
SERVOPACK as soon as the input voltage of the speed reference (V-REF) drops below the motor speed level in
the zero clamp level (Pn501). The servomotor ignores the speed reference and then quickly stops and locks the
servomotor.
The servomotor is clamped within
±1 pulse of when the zero clamp function is turned ON, and will still return to
the zero clamp position even if it is forcibly rotated by external force.
Pn305 Soft Start Acceleration Time
Setting Range Setting Unit Factory Setting Setting Validation
0 to 10000 ms 0 Immediately
Pn306 Soft Start Deceleration Time
Setting Range Setting Unit Factory Setting Setting Validation
0 to 10000 ms 0 Immediately
The soft start function enables smooth speed control when inputting a stepwise speed reference or when selecting internally
set speeds. Set both Pn305 and Pn306 to “0” for normal speed control.
Set these parameters as follows:
• Pn305: The time interval from the time the motor starts until the motor maximum speed is reached.
• Pn306: The time interval from the time the motor is operating at the motor maximum speed until it stops.
Speed
Speed
Pn305 Pn306
After soft start
Maximum speed of Servomotor
Before soft start
Pn307 Speed Reference Filter Time Constant
Setting Range Setting Unit Factory Setting Setting Validation
0 to 65535
(0 to 655.35 ms)
0.01 ms 40
(0.40 ms)
Immediately
This smoothens the speed reference by applying a 1st-order delay filter to the analog speed reference (V-REF) input.
A value that is too large, however, will slow down response.
Speed
Host controller
When the /ZCLAMP signal is turned ON, a
speed reference below the Pn501 setting is detected.
Speed reference
V-REF
Zero clamp
/P-CON
(/ZCLAMP)
Stops precisely!