WEG CFW08 Vector inverter User Manual page 79

DETAILED PARAMETER DESCRIPTION
Parameter
(1)
P142
Maximum Output
Voltage
(1)
P145
Field Weakening
Frequency
(F )
nom
These
parameters are
only available in
V/F control
(P202=0 or 1)
(1)
This parameter can be changed only with the inverter disabled (motor stopped).
78
Range
[factory Setting]
Unit Description / Notes
To set the parameter P138 use the following procedure:
- run the motor without load up to approximately half of the application
- measure the actual motor or equipment speed;
- apply rated load to equipment;
- increase parameter P138 until the speed reaches its no-load speed.
Define the V/F curve used in V/Fcontrol (P202=0 or 1).
0...100%
These parameters allow changing the standard V/F curve defined
at P202 - programmable V/F curve.
[ 100% ]
P142 sets the maximum output voltage. This value is set
1%
as a percent of the inverter supply voltage.
Parameter P145 defines the rated frequency of the motor used.
P133...P134
The V/F curve relates the inverter output voltage and frequency
[ 60.00Hz ]
(applied to the motor) and consequently the magnetizing flux of the
0.01Hz (<100.0)
motor.
0.1Hz (>99.99)
The programmave V/F curve can be used in special applications
where the motors used require a rated voltage and/or frequency
different than the standard ones. Examples: motor for 220V/
400Hz and a motor for 200V/60Hz.
Parameter P142 is also useful in appplications that require
rated voltage different from the inverter supply voltage. Example:
440V line and 380V motor.
Output Voltage
Figure 6.10 - V/F curve with slip compensation
top speed;
Output Voltage
P142
0
0.1Hz
Figure 6.11 - Adjustable V/F curve
(function of
the motor
load)
Output
Frequency
Output
Frequency
P145