Lenze 8400 StateLine - Manual (Page 204)

5 Motor control (MCTRL)
5.9 Parameterisable additional functions
204
Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14
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Lowering the switching frequency due to high heatsink temperatures
Exceeding the maximally permissible heatsink temperature would lead to an inhibited drive due to
the "Overtemperature" error and a torquelessly coasting motor. Therefore, if the Lenze setting is
selected, the switching frequency is reduced to the next frequency below when the heatsink
temperature has risen to 5 °C below the maximally permissible temperature. After the heatsink has
cooled down, the controller automatically switches to the next frequency above until the set
switching frequency is reached.
Switching frequency reduction due to high heatsink temperature can be deactivated via
C00144 . If
the switching frequency reduction is deactivated, the "oH1: Heatsink overtemperature" error
message will be issued when the maximally permissible heatsink temperature is reached. An "Error"
response is the result and the motor is coasting.
Lowering of the switching frequency depending on the output current
"Variable" switching frequencies can be selected for the controller in
C00018 , where the controller
automatically lowers the switching frequency depending on the controller output current. The
modulation mode will not be changed.
When a "fixed" switching frequency is selected, no switching frequency changeover takes place. In
case of fixed frequencies, the controller output current is limited to the permissible value of the
corresponding switching frequency. In case of larger load impulses, the overcurrent interruption
may be activated, to which the controller responds with "Error".

Note!
Switching frequency for the motor parameter identification
Up to and including version 13.xx.xx , the motor parameter identification is executed
with a switching frequency of 4 kHz.
• Thus, a motor parameter identification is not permissible for the previously
mentioned example as the sinusoidal filter may only be operated with a minimum
switching frequency of 8 kHz!
From version 14.00.00 , the motor parameter identification can also be executed with a
switching frequency of 8 kHz instead of 4 kHz. For this purpose, the option "Motor ident.:
Switching frequency 8 kHz" (Bit 4 = "1") has to be set in C02864/1 .
• With this setting, a motor parameter identification would be permissible for the
previously mentioned example.
Generally, a switching frequency of 4 kHz is recommended for the motor parameter
identification as it serves to obtain the most accurate results.
 Automatic motor data identification ( 111)
Parameter Info Lenze setting
C00144 Switching frequency reduction (temp.) 1: On

The changeover thresholds are listed in the 8400 hardware manual in the rated data.
The hardware manual has been stored in electronic form on the data carrier supplied
with the 8400 controller.