WEG CFW700, Programming And Troubleshooting Manual

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9
Scalar Control (V/f)
CFW700 | 9-1
9 SCALAR CONTROL (V/f)
It consists of a simple control based on a curve that links output voltage and frequency. The inverter operates
as a voltage source, generating frequency and voltage values according to that curve. It is possible to adjust this
curve to standard 50 Hz or 60 Hz motors or to special ones through the adjustable V/f curve. Refer to the block
diagram at the
figure 9.1 .
The advantage of the V/f control is that due to its simplicity just a few settings are necessary. The start-up is fast
and simple, and the factory settings require generally few or no modifications.
V
V
Reference
PWM
PWM
Speed
P0202=2=Ajustable V/f
P0202=Type of Control
Total Reference
(Refer to figure 13.7 )
I
s
= Output Current
TRANSF
.
I active
P0139
V
f
P0202=0 or 1=V/f
P0142
P0143
P0144
P0138
P0137
Speed
Speed
Speed
P0146 P0145
Automatic Torque
BOOST
Slip
Compensation
V V
V
P0136
Figure 9.1: V/f control block diagram