Voltage Ctrl; Brake Chopper - ABB ACS850 Firmware Manual

180 Parameters
No. Name/Value
47

47 Voltage ctrl

47.01 Overvolt ctrl
Disable
Enable
47.02 Undervolt ctrl
Disable
Enable
48

48 Brake chopper

48.01 Bc enable
Disable
EnableTherm
Enable
48.02 Bc run-time ena
Const
Pointer
48.03 BrThermTimeConst Defines the thermal time constant of the brake resistor for
0 ... 10000 s
48.04 Br power max cnt
Description
Overvoltage and undervoltage control settings.
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 a brake chopper and resistor or a regenerative supply
section are included in the drive, the controller must be
disabled.
Overvoltage control disabled.
Overvoltage control enabled.
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
stop. This will act as a power-loss ride-through functionality in
systems with high inertia, such as a centrifuge or a fan.
Undervoltage control disabled.
Undervoltage control enabled.
Control of the brake chopper.
Enables the brake chopper control.
Note: Before enabling the brake chopper control, ensure that
a brake resistor is connected and the overvoltage control is
switched off (parameter
Brake chopper control disabled.
Brake chopper control enabled with resistor overload
protection.
Brake chopper control enabled without resistor overload
protection. This setting can be used, for example, if the
resistor is equipped with a thermal circuit breaker that is wired
to stop the drive if the resistor overheats.
Selects the source for quick run-time brake chopper control.
0 = Brake chopper IGBT pulses are cut off
1 = Normal brake chopper IGBT modulation. The overvoltage
control is automatically switched off
This parameter can be used to program the chopper control
to function only when the drive is operating in the generator
mode.
Bit pointer setting (see Terms and abbreviations
overload protection.
Brake resistor thermal time constant.
Defines the maximum continuous braking power which will
raise the resistor temperature to the maximum allowed value.
The value is used in the overload protection.
47.01 Overvolt ctrl).
FbEq
0
1
0
1
0
1
2
on page 63). -
1 = 1 s