78 Program featuresSettingsParameters 01.11 DC voltage (page 115), 30.30 Overvoltage control (page 254),30.31 Undervoltage control (page 254), 95.01 Supply voltage (page 388), and 95.02Adaptive voltage limits (page 388). Brake chopperA brake chopper can be used to handle the energy generated by a deceleratingmotor. When the DC voltage rises high enough, the chopper connects the DC circuitto an external brake resistor. The chopper operates on the pulse width modulationprinciple.The internal brake choppers of ACS880 drives start conducting when the DC linkvoltage reaches 1.156 × UDCmax . 100% pulse width is reached at approximately 1.2 ×UDCmax , depending on supply voltage range – see table under Voltage control andtrip limits above. (UDCmax is the DC voltage corresponding to the maximum of the ACsupply voltage range.) For information on external brake choppers, refer to theirdocumentation.Note: For runtime braking, overvoltage control (parameter 30.30 Overvoltage control)needs to be disabled for the chopper to operate.SettingsParameters 01.11 DC voltage (page 115) and 30.30 Overvoltage control (page 254);parameter group 43 Brake chopper (page 307).Supply voltage range [V] (see 95.01 Supply voltage)Level 208…240 380…415 440…480 500 525…600 660…690Overvoltage fault limit 489/440* 800 878 880 1113 1218Overvoltage control limit 389 700 778 810 1013 1118Internal brake chopper at 100%pulse width 403 697 806 806 1008 1159Internal brake chopper at 0%pulse width 375 648 749 780 936 1077Overvoltage warning limit 373 644 745 776 932 1071DC voltage at upper bound ofsupply voltage range (UDCmax ) 324 560 648 675 810 932DC voltage at lower bound ofsupply voltage range 281 513 594 675 709 891Undervoltage control and warninglimit 239 436 505 574 602 757Charging activation/standby limit 225 410 475 540 567 713Undervoltage fault limit 168 308 356 405 425 535*489 V with frames R1…R3, 440 V with frames R4…R8.
