Operating Instruction - Frequency Inverter 230V / 400V ... - opis.cz

17 Special FunctionsThe configurable functions of the corresponding control methods enable another fieldof application of the frequency inverters. The integration in the application is madeeasier by special functions.17.1 Pulse Width ModulationThe motor noises can be reduced by changing over the parameter Switching Frequency400. The maximum reduction of the switching frequency should not exceed aratio of 1:10 to the frequency of the output signal for a sine-shaped output signal. Themaximum possible switching frequency depends on the drive output and the ambientconditions. For the required technical data refer to the corresponding table and thedevice type diagrams.ParameterSettingsNo. Description Min. Max. Fact. sett.400 Switching frequency 2 kHz 16 kHz 4 kHz1)The factory setting of the parameter Switching Frequency 400 depends on theselected parameter Configuration 30.- Configurations 1xx => Switching Frequency 400 = 2 kHz- Configurations 2xx / 4xx => Switching Frequency 400 = 4 kHzThe heat losses increase proportionally to the load point of the frequency inverter andthe switching frequency. The automatic reduction adjusts the switching frequency tothe current operating state of the frequency inverter in order to provide the outputperformance required for the drive task at the greatest possible dynamics and a lownoise level.The switching frequency is adjusted between the limits which can be set via parametersSwitching frequency 400 and Min. Switching Frequency 401. If the Min. SwitchingFrequency 401 is larger than or equal to the Switching Frequency 400, theautomatic reduction is deactivated.ParameterSettingsNo. Description Min. Max. Fact. sett.401 Min. Switching Frequency 2 kHz 16 kHz 2 kHzThe change of the switching frequency depends on the heat sink temperature switchofflimit and the output current.The temperature limit to be exceeded so that the switching frequency is reduced canbe set via parameter Reduction Limit Heat Sink Temp. 580. If the heat sink temperaturefalls below the threshold set via parameter Reduction Limit Heat Sink Temp. 580by 5 °C, the switching frequency is increased again step by step.ParameterSettingsNo. Description Min. Max. Fact. sett.580 Reduction Limit Heat Sink Temp. -25 °C 0 °C -4 °CNote:The limit for the switching frequency reduction is influenced by theintelligent current limits depending on the selected Operation Mode573 and the output current. If they have been switched off or providethe full overload current, the switching frequency is reduced when theoutput current exceeds the limit of 87.5% of the long-term overloadcurrent (60s). The switching frequency is increased if the output currentdrops below the reference current of the next highest switchingfrequency.02/06 161