LG C Series - Manual (Page 86)

Chapter 10. Advanced functions
Example
Rated frequency= 60Hz
Rated motor RPM= 1740rpm
Motor pole number= 4
Hz f
s
2
120
4 1740
60
= ⎟
⎠
⎞
⎜
⎝
⎛ ×
− =
H32- [Rated slip frequency] is 2Hz. Set H32- [Rated slip frequency] to 2.

H33: Enter the motor nameplate rated current

H34: Enter the measured current when the motor is running at rated frequency after
the load is removed. Enter 50% of the rated motor current when it is difficult to
measure the motor no load current.

H36: Enter motor efficiency on the nameplate.

H37: Select load inertia based on motor inertia as shown below.
0 Less than 10 times motor inertia
1 About 10 times motor inertia
H37 [Load inertia rate]
2
Greater than 10 times motor
inertia
 As the loads are heavier, the speed gap between rated RPM and synchronous speed
is widening (see the figure below). This function compensates for this inherent slip.
Set the Torque boost value within 2%. Setting it too high may cause motor over-
energizing and lead to error in calculating slip speed.
Synchronous
speed
Motor rated
RPM
RPM
Load
Slip
compensation
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