ABB ACS880-x04, Firmware Manual, Page: 269 / 604

Parameters 269
30.30 Overvoltage control Enables the overvoltage control of the intermediate DC link.
Fast braking of a high inertia load causes the voltage to rise to
the overvoltage control limit. To prevent the DC voltage from
exceeding the limit, the overvoltage controller automatically
decreases the braking torque.
Note: If the drive is equipped with a brake chopper and
resistor, or a regenerative supply unit, the controller must be
disabled.
Enable
Disable Overvoltage control disabled. 0
Enable Overvoltage control enabled. 1
30.31 Undervoltage
control Enables the undervoltage control of the intermediate DC link.
If the DC voltage drops due to input power cut off, the
undervoltage controller will automatically decrease the motor
torque in order to keep the voltage above the lower limit. By
decreasing the motor torque, the inertia of the load will cause
regeneration back to the drive, keeping the DC link charged
and preventing an undervoltage trip until the motor coasts to a
stop. This will act as a power-loss ride-through functionality in
systems with high inertia, such as a centrifuge or a fan. Enable
Disable Undervoltage control disabled. 0
Enable Undervoltage control enabled. 1
30.35 Thermal current
limitation Enables/disables temperature-based output current limitation.
The limitation should only be disabled if required by the
application. Enable
Disable Thermal current limitation disabled. 0
Enable Thermal current limitation enabled. 1
30.101 LSU limit word 1 (Only visible when IGBT supply unit control activated by
95.20 )
Displays limit word 1 of the supply unit.
This parameter is read-only.
-
0000h…FFFFh Supply unit limit word 1. 1 = 1
No. Name/Value Description Def / FbEq16
Bit Name Description
0 P user ref max 1 = Power reference is being limited by supply control program
parameters
1 P user ref min
2 P user max 1 = Power is being limited by parameter 30.149
3 P user min 1 = Power is being limited by parameter 30.148
4 P cooling
overtemp 1 = Power reference is being limited because of coolant
overtemperature
5 P power unit
overtemp 1 = Power reference is being limited because of supply unit
overtemperature
6…15 Reserved