SV-iS7 User Manual - Inverter Drive Supermarket

Chapter 8 Applied Functions
8.1.7 Slip compensation operation
For an induction motor, the difference between the rotation speed of the motor and the set frequency varies according to
the load ratio. The slip compensation operation is used for the load that should compensation the speed difference(slip). If
the control mode is sensorless or vector or V/F PG, the speed difference is automatically compensation.
Group Code No. Function Display Setting Display Unit
DRV
BAS
09 Control Mode 2 Slip Compen -
14 Motor Capacity 2 0.75(0.75Kw base) kW
11 Pole Number - 4 -
12 Rated Slip - 90(0.75Kw base) rpm
13 Rated Curr - 3.6(0.75Kw base) A
14 Noload Curr - 1.6(0.75Kw base) A
16 Efficiency - 72(0.75Kw base) %
17 Inertia Rate - 0(0.75Kw base) -
DRV-09 Control Mode (control mode) : checks whether the control mode is set at No. 2 Slip Compen.
DRV-14 Motor Capacity (motor capacity) : sets the capacity of the motor connected to the inverter output.
BAS-11 Pole Number (pole number) : inputs the number of poles on the plate of the motor.
BAS-12 Rated Slip (rated slip) : input by using the rated revolution on the plate of the motor.
BAS-13 Rated Curr (rated current) : inputs the rated current on the plate of the motor.
BAS-14 Noload Curr (no-load current) : inputs the current measured when the motor operates at the rated frequency
after the load device connected to the motor axis is removed. If no-load current is hard to measure, input the current
30~50% of the current on the plate of the motor.
BAS-16 Efficiency (motor efficiency) : inputs the efficiency on the plate of the motor.
BAS-17 Inertia Rate (load inertia ratio) : selects the load inertia on the basis of the inertia of the motor.
(0: when it is less than 10 times of motor’s inertia, 1: when it is 10 times of motor’s inertia, 2~8: when it is more than 10
times of motor’s inertia)
⎛ rpm × P ⎞
s = f − ⎜ ⎟ , f s =rated slip frequency, f r =rated frequency, rpm=rated revolution of motor, P =motor poles
⎝ 120 ⎠
f r
Rotation
speed
Synchroni
zed speed
Rotation
speed of
motor
⎛ 1740×
4 ⎞
ex) rated frequency: 60Hz, rated revolution: 1740rpm, pole numbers: 4. f s = 60 − ⎜ ⎟ = 2Hz
⎝ 120 ⎠
Load
ratio
Slip offset
control
8-11