Sigma II User’s Manual
Chapter 6: Servo Adjustment
6-5
6.1.4
Adjusting Offset
The servo system does not operate smoothly if reference voltage from the host con-
troller or external equipment has a reference offset value close to 0V. In that case,
adjust the reference offset value to 0V.
n
Reference Voltage Offset from Host Controller or External
Circuitry
n
Reference Offset Adjustment
The following two methods are provided to reset the reference offset value to 0V.
•
Reference offset automatic adjustment
•
Reference offset manual adjustment
If a position loop is formed in the host controller, be sure to make a manual offset
adjustment and do not make automatic reference offset adjustment.
Refer to the following sections in Chapter 7 Using the Digital Operator for a
detailed description of reference offset adjustment.
6.1.5
Setting the Torque Reference Filter Time Constant
If there is machine vibration which may be caused by the servodrive, try adjusting
the filter time constant in Pn401. This may stop the vibration.
The above constant is the filter time constant of the torque reference to be set in the
servo amplifier. The smaller the value, the faster the speed control response will be.
There is, however, a limit, depending on machine conditions.
Adjustment Method
Detailed Description
Automatic
7.2.3 Automatic Adjustment of the Speed and Torque Reference Offset
Manual
7.2.4 Manual Adjustment of the Speed and Torque Reference Offset
Parameter
Signal
Setting
(x 0.01ms)
Application
Pn401
Torque Reference Filter Time
Constant
Setting Range: 0 to 65535
Default Setting: 100
Speed/Torque Control,
Position Control
Offset
Offset adjustment
Reference speed
or reference
torque
Reference
voltage
Reference
voltage
Reference speed
or reference
torque
Make offset
adjustment with the
servo amplifier