WEG CFW-10 EASYDRIVE User Manual page 75

[Factory Setting]
Parameter
P288
Frequency Fx
0.1Hz (<100Hz);
P290
Current Ix
P295
Inverter Rated
current
(I )
nom
(1)
P297
Switching
Frequency
(1)
This parameter can be changed only with disabled inverter (stopped motor).
CHAPTER 6 - DETAILED PARAMETER DESCRIPTION
Range
Unit
When the definition in the function name is true, the digi-
tal output will be activated, i.e., the relay coil is energized.
When the option 'Not used' has been programmed, the
relay output(s) will be disabled, i.e., the coil is not
energized.
Definitions of the used symbols in the functions:
0.0 to 300Hz Used in the relay output functions Fs>Fx, Fe>Fx e Is>Ix
[ 3.0Hz ] (see P277).
1Hz (>99.9Hz)
0 to 1.5xP295
[ 1.0xP295 ]
0.1A
1.6 to 7.3
[ According to
Inverter Rated
Current ]
-
Defines the switching frequency of the IGBTs in the inveter.
2.5 to 15.0
The switching frequency is a comprimise between the
[ 5 kHz ]
motor acoustic noise level and the inverters IGBTs losses.
0.1 kHz
Higher switching frequencies cause lower motor acoustic
noise level, but increase the IGBTs losses, increasing the
drive components temperature and thus reducing their
useful life.
The predominant frequency on the motor is twice the
switching frequency setat P297.
Thus, P297=5kHz results in an audible motor noise
corresponding to 10kHz. This is due to the used PWM
technique .
The reduction of the switching frequency also contributes
to the reduction of instability and ressonance that may
occur in certain application conditions, as well as reduces
the emission of electromagnetic energy by the inveter.
The reduction of the switching frequencies also reduces
the leakage currents to ground.
Use currents according to table below:
Description / Notes
Fs = P005 - output frequency (motor)
Fe = Reference frequency (ramp input frequency)
Fx = P288 - Fx frequency
Is = P003 - output current (motor)
Ix = P290 - Ix current
P295
1.6
2.6
4.0
7.3
Inverter Rated
Current (I )
nom
1.6A
2.6A
4.0A
7.3A
75