KFU 2-/4-
221
The parameter
Trigger threshold
507
is to be set in such a way that it is between the
maximum DC link voltage which the mains can generate and the maximum admissi-
ble DC link voltage of the frequency inverter.
max
dMC
Netz
Ud
U
2
1,1
U
If the parameter
Trigger threshold
507
is set larger than the maximum admissible DC
link voltage, the motor chopper cannot become active, the motor chopper is switched
off.
If the set
Trigger threshold
507
is smaller than the maximum DC link voltage the
mains can generate, error message F0706 (chapter "Error Messages") is displayed
when the frequency inverter is switched on.
17.7.2 Temperature
Adjustment
The field-orientated control systems are based on the most precise calculation of the
machine model possible. The rotor time constant is an important machine variable for
the calculation. The figure to be read out via the parameter
Current rotor time con-
stant
227
is calculated from the inductivity of the rotor circuit and the rotor resistance.
The dependence of the rotor time constant on the motor temperature can be taken
into account in the case of particularly high precision requirements via a suitable
measurement. Via
Operation mode
465
for the temperature adjustment, you can se-
lect different methods and actual value sources for temperature measurement.
Operation mode
465
Function
0 -
Off
The function is deactivated.
1 -
Temp. meas. on MFI1A
Temperature synchronization
(0 ... 200
°
C => 0 ... 10 V / 0 ... 20 mA),
actual temperature value at multifunctional input 1
4 -
Temp. Meas. at Start
Determination of temperature by frequency in-
verter via measurement of the winding resistance
without external temperature measurement
11 -
Vectron temp. meas. on
MFI1A
Temperature synchronization; act. temperature
value across analog multi-function input.
(-26.0 °C … 207.8 °C => 0 ... 10 V / 0 ... 20 mA)
Operation mode 1 requires an external temperature measurement system which eva-
luates the temperature sensor and maps the temperature range from 0...200 °C to an
analog voltage or current signal. The
Operation mode
452
of multifunction input MFI1
must be selected accordingly.
Operation mode 4 is available in configurations 210, 211 and 230. When the signals
Controller release and Start clockwise or Start anticlockwise are present, the motor
temperature and the rotor time constant are synchronized by means of the measured
winding resistance.
For operation mode 11, an optional temperature measurement board by your supplier
is required. This board can be connected to the 20 V power supply on the frequency
inverter. This board converts the temperature to an analog voltage or current signal in
a range from -26.0 °C to 207.8 °C. The resistance of the measuring resistor
KTY84/130 to be used is 1000
Ω
at a temperature of 100 °C.
