1-5
• Custom V/f pattern can be set.
H Frequency References
• The following five types of frequency references can be used to control the output frequency of the
Inverter.
S Numeric input from the Digital Operator
S Voltage input within a range from 0 to 10 V
S Voltage
input within a range from 0 to
±
10 V (With minus
voltage, rotation is in the opposite direc
-
tion of the run command.)
S Current input within a range from 4 to 20 mA
S Input by Optional Card
The Inverter can be set to use any of the above types by designating it with parameters.
• A maximum of eight frequency references can be registered in the Inverter. Including inching, this
enables multi-step speed operation with up to nine speed steps via remote multi-step reference
inputs.
H PID Control
• The Inverter has a PID control function, enabling easy follow-up control.
• Follow-up
control is a control method
in which the Inverter varies the output frequency to match the
feedback value from the sensor with the set target value.
• Follow-up control can be applied to a variety of control operations, depending on the contents
detected by the sensor.
• PID control is available for the following applications.
S Speed control: With
a speed sensor
, such as a
tacho-generator
, the Inverter regulates the
rotation
speed of the motor regardless of the load of the motor or synchro
-
nizes the rotation speed of the motor with that of another motor.
S Pressure control: With a pressure sensor, the Inverter performs constant pressure control.
S Flow-rate control: By sensing the flow rate of a fluid, the Inverter performs precise flow-rate
control.
S Temperature control: With a temperature sensor, the Inverter performs temperature control by
fan speed.
H Zero-servo Control
• This function is valid with vector control (with PG).
• Even
at a motor speed of zero (0
Hz), a torque of 150% of the motor
’
s rated torque can be generated
and the average servomotor holding power (stopping power) can be obtained.
H Speed Control By Feedback
• This function is valid with PG.
• An
optional PG Speed Control Card be used to enable feedback control for
speeds, thereby improving
speed control accuracy.
Introduction Chapter
1