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Functions
7.7 Protection functions
Inverter with CU240B-2 and CU240E-2 Control Units
Operating Instructions, 07/2010, FW 4.3.2, A5E02299792B AA
175
Table 7- 16 The most important torque control parameters
Parameter Description
P1300 = … Control type:
20: Vector control without speed encoder
22: Torque control without speed encoder
P0300 …
P0360
Motor data are transferred from the motor rating plate during the quick commissioning
and calculated with the motor data identification
P1511 = … Additional torque
P1520 = … Upper torque limit
P1521 = … Lower torque limit
P1530 = … Motoring power limit
P1531 = … Regenerative power limit
Additional information about this function is provided in the parameter list and in function
diagrams 6030 onwards in the List Manual.
7.7
Protection functions
The frequency inverter offers protective functions against overtemperature and overcurrent
for both the frequency inverter as well as the motor. Further, the frequency inverter protects
itself against an excessively high DC link voltage when the motor is regenerating.
The load torque monitoring functions provide effective plant and system protection.
7.7.1
Inverter temperature monitoring
The inverter temperature is essentially determined by the resistive losses of the output
current and the switching losses which occur when pulsing the Power Module. The inverter
temperature falls when either the output current or the pulse frequency of the Power Module
is reduced.
I2t monitoring (A07805 - F30005)
The Power Module's I2t monitoring controls the inverter utilization by means of a current
reference value. The utilization is specified in r0036 [%].
Monitoring the chip temperature of the power unit (A05006 - F30024)
The temperature difference between the power chip (IGBT) and heat sink is monitored using
A05006 and F30024. The measured values are specified in r0037[1] [°C].
Heat sink monitoring (A05000 - F30004)
The power unit heat sink temperature is monitored using A05000 and F30004. The values
are specified in r0037[0] [°C].