beautypg.com

4 soft start, 5 speed reference filter, 6 using the zero clamp function – Yaskawa SGDH Linear Sigma Series User Manual

Page 285

background image

9.7 Operating Using Speed Control with Analog Reference

9-41

9

9.7.4 Soft Start

The soft start function converts the stepwise speed reference inside the SERVOPACK to a consistent rate of
acceleration and deceleration.

9.7.5 Speed Reference Filter

9.7.6 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 SERVO-
PACK as soon as the input voltage of the speed reference (V-REF) drops below the motor speed level in the zero
clamp level (Pn580). The servomotor ignores the speed reference and then quickly stops and locks the servomo-
tor.
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 moved 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

(0.00 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

YASKAWA

YASKAWA

SERVOPACK

SGDH-

MODE/SET

CHARGE

POWER

DATA/

Host

controller

When the /ZCLAMP signal is turned ON, a

speed reference below the Pn580 setting is

detected

Speed reference

Stops

precisely!

V-REF

/P-CON

(/ZCLAMP)

Zero clamp