LG Electronics SV-iC5 Series Advanced functions, = −  rpm ⋅ P  f s f r  120   , = 2 Hz

10. Advanced functions

H32 : Enter the slip frequency based on the following formula and motor nameplate.

= −  rpm ⋅ P  f s f r  120 

 

Where, fs = Rated slip frequency

fr = Rated frequency

rpm = Motor nameplate RPM

P= Number of Motor poles

Example

Rated frequency= 60Hz

Rated motor RPM= 1740rpm

Motor pole number= 4

 1740 ⋅ 4 
fs = 60 − 	120		= 2Hz
		

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.

H37	[Load inertia rate]	0	Less than 10 times motor inertia
		1	About 10 times motor inertia
		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.

RPM
Synchronous
speed
	Slip
	compensation
Motor rated
RPM
Load
10-7	SV-iC5