Setting functions
8.7 Protection and monitoring functions
Converter with control units CU250D-2
Operating Instructions, 04/2014, FW V4.7, A5E34261542B AA
209
Protection and monitoring 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.
Inverter temperature monitoring
The inverter temperature is essentially defined by the following effects:
● The ambient temperature
● The ohmic losses increasing with the output current
● Switching losses increasing with the pulse frequency
The inverter monitors its temperature using the following monitoring types:
● I
2
t monitoring (alarm A07805, fault F30005)
The I
2
t monitoring calculates the inverter utilization on the basis of a current reference
value predefined by the factory.
– Actual current > reference value: The actual value of the utilization increases.
– Actual current < reference value: The actual value of the utilization decreases or
remains = 0.
● Measuring the chip temperature of the Power Module (alarm A05006, fault F30024)
● Measuring the heat sink temperature of the Power Module (alarm A05000, fault F30004)
Inverter response to thermal overload
2
Power unit temperatures [°C]
p0290
Power unit overload response
Factory setting and the ability to be changed depends on the hardware. The dependency
is described in the List Manual.
A thermal overload is present if the inverter temperature is greater than that specified in
p0292.
You define how the inverter responds if there is a risk of thermal overload using this
parameter. The details are described below.
p0292
Power unit temperature warning threshold
(factory setting: Heat sink [0] 5 °C, power
semiconductor [1] 15 °C)
The value is set as a difference to the shutdown temperature.
Power unit warning at I2t overload (factory setting: 95 %)
To Next Page
Loading...
