Operating Instructions ACU
14 Error behavior and warning behavior
Operation of the frequency inverter and the connected load are monitored continuously. The
monitoring functions are to be parameterized with the corresponding limit values specific to the
application. If the limits were set below the switch-off limit of the frequency inverter, an error
switch-off can be prevented by suitable measures if a warning message is issued.
The warning message is displayed by the LED's and can be read out on the operating unit via
parameter Warnings 269 or output via one of the digital control outputs.
14.1 Overload Ixt
The admissible load behavior depends on various technical data of the frequency inverters and the
ambient conditions.
The selected Switching Frequency 400 defines the rated current and the available overload for one
second and sixty seconds, respectively. The Warning Limit Short Term Ixt 405 and Warning Limit
Long Term Ixt 406 are to be parameterized accordingly.
Warning Limit Short Term Ixt
Warning Limit Long Term Ixt
Reaching of warning limits is reported via digital signals.
Warning Limit Short Term Ixt 405 or
Warning Limit Long Term Ixt 406 was reached.
1)
For linking to frequency inverter functions
2)
For output via a digital output.
14.2 Temperature
The ambient conditions and the energy dissipation at the current operating point result in the
frequency inverter heating up. In order to avoid a fault switch-off of the frequency inverter, the
Warning Limit Inside Temp. 407 for the heat sink temperature and the Warning Limit Heat Sink
Temp. 408 as an internal temperature limit are to be parameterized. The temperature value at
which a warning message is output is calculated from the type-dependent temperature limit minus
the adjusted warning limit.
The switch-off limit of the frequency inverter for the maximum temperature is an internal
temperature of 65 °C and a heat sink temperature of 80°C – 90°C.
Warning Limit Heat Sink Temp.
Warning Limit Inside Temp.
Minimum temperatures are defined as -10 °C (interior) and 30 °C for the heat sink
temperature.