Siemens SINAMICS G110D, Руководство по эксплуатации

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Functions
6.8 Protection functions
SINAMICS G110D
126
Operating Instructions, 07/2016, FW V3.63, A5E36768472B AB
6.8.3 Overcurrent protection
Method of operation
The maximum current controller (I
max
controller) protects the motor and inverter against
overload by limiting the output current. The I
max
controller is only active with V/f control.
If an overload situation occurs, the speed and stator voltage of the motor are reduced until
the current is within the permissible range. If the motor is in regenerative mode, i.e. it is
being driven by the connected machine, the I
max
controller increases the speed and stator
voltage of the motor to reduce the current.
Note
The inverter load is only reduced if the frequency is reduced with a lower load and at lower
speeds (e.g. parabolic torque-speed characteristic of the motor load).
In the regenerative mode, the current only decreases if the torque decreases at a higher
frequency.
Settings
Note
The factory setting of the I
max
controller only needs to be changed in exceptional cases by
appropriately trained personnel.
Table 6- 34 I
max
controller parameters
Parameter Description
P0003 = 3 User access level
3: Expert
P0305 = … Rated motor current
P0640 = … Maximum permissible motor overload referred to P0305 rated motor current
P1340 = … Proportional gain of controller for frequency reduction
P1341 = … Integral time of controller for frequency reduction
P1345 = … Proportional gain of controller for voltage reduction
P1346 = … Integral time of controller for voltage reduction
r0056 bit13 Status: I
max
controller active
r1343 Frequency output of I
max
controller
Shows the amount to which the I-max controller reduces the inverter output frequen-
cy.
r1344 Voltage output of I
max
controller
Shows the amount by which the I-max controller reduces the inverter output voltage.
For more information about this function, see function diagram 6100 in the List Manual.