KEB COMBIVERT F4-S/1.2, Applications Manual, Page: 40 / 96

uF - Parameter
40
The U/f - curve is adjusted with uF. 0 and uF. 1.
uF.0 indicates the output frequency where an output voltage of 100% is reached.
100% output voltage means a value of UDC /
√
2 when uF. 8 is switched off. With an
active UDC-compensation 100% results in the adjusted output voltage and a max of
1.05 * UDC/
√
2 . UDC means dc-bus voltage. The dc-bus voltage results from: UDC =
√
2 * input voltage.
The boost specfies the output voltage at an output frequency of 0Hz. The presetting
occurs as a percentage value.
Output Voltage
Output Frequency
Rated Frequency
(uF. 0)
0
Boost
(uF. 1)
100%
To overcome larger breakaway torque raise the output voltage, from 0 Hz to a time set
in u.5. These voltage increases are called delta boost. They are preset with a
resolution of 0,1% with uF. 4. If the sum of boost + delta boost exceed a value of
25,5%, then the delta boost is internally limited to 25,5% boost.
Output Voltage
Time
0
Boost
(uF. 1)
100%
Delta-Boost (uF. 4)
Voltage/Frequency
Characteristic
(uF. 0, uF. 1)
Delta Boost
(uF. 4, uF. 5)