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

17.4 Brake Chopper and Brake ResistanceThe frequency inverters feature a brake chopper transistor. The external brake resistoris connected to terminals Rb1 and Rb2. The parameter Trigger Threshold 506defines the switch-on threshold of the brake chopper. The generator output of thedrive, which leads to the increase in the DC link voltage, is converted to heat by theexternal brake resistor above the limit set via parameter Trigger Threshold 506.ParameterSettingsNo. Description Min. Max. Fact. sett.506 Trigger Threshold U dmin +25V 1000.0 V U dBCDefault settings of parameter Trigger Threshold 506:- 385 V for ACT series of devices ACT 201–05 to –15- 770 V for ACT series of devices ACT 401–05 to –39The parameter Trigger Threshold 506 is to be set in such a way that it is betweenthe maximum DC link voltage which the mains can generate and the maximum admissibleDC link voltage of the frequency inverter.UNetz⋅ 1.1⋅2 < UdBC< UdmaxIf the parameter Trigger Threshold 506 is set larger than the maximum admissibleDC link voltage, the brake chopper cannot become active, the brake chopper isswitched off.If the parameter Trigger Threshold 506 is set to a value below the DC link voltagegenerated by the mains, error message F0705 (chapter "Error Messages") is displayedif the start command is issued to the frequency inverter.If the DC link voltage exceeds the maximum values of 400 V for the ACT 201 series ofdevices and 800 V for the ACT 401 series of devices, respectively, error messageF0700 is displayed (chapter "Error Messages").164 02/06