Dynamic Braking - WEG CFW100 Programming Manual

MOTOR CONTROL
WARNING!
!
The DC Braking can continue acting even if the motor has already stopped. Be careful with the
thermal dimensioning of the motor for short-period cyclic braking.
P301 - DC Braking Frequency
Range:
Properties:
Description:
This parameter establishes the initial point to apply the DC Braking at the stop when the inverter is disabled by
ramp, according to
P302 - DC Braking Current
Range:
Properties:
Description:
This parameter sets the DC current (DC braking torque) applied to the motor during the braking.
The setting must be done by gradually increasing the value of P302, which varies from 0.0 to 100.0 % of the rated
braking voltage, until the desired braking is obtained.
If the inverter has a power too much higher than the motor, the braking torque will be too low. On the other hand, if
the opposite is true, overcurrent may occur during the braking, as well as overheating of the motor. A value too high
in P302 may cause overcurrent faults on the inverter and even damages to the connected motor by overcurrent on
the windings.
8
✓
NOTE!
A value too high in P302 may cause overcurrent faults on the inverter and even damages to the
connected motor by overcurrent on the windings.

8.1.5 Dynamic Braking

The braking torque that can be obtained through the application of frequency inverters without dynamic braking
resistors varies from 10 % to 35 % of the motor rated torque.
In order to obtain higher braking torques, resistors for dynamic braking are used. In this case the regenerated
energy is dissipated on the resistor mounted externally to the inverter.
This type of braking is used in the cases when short deceleration times are wished or when high inertia loads are
driven.
✓
NOTE!
The Dynamic Braking function can only be used if a braking resistor has been connected to the
inverter, and if the parameters related to it have been adjusted properly.
P153 - Dynamic Braking Level
Range:
Properties:
Description:
8-12 | Micro Mini Drives
0.0 to 15.0 Hz
V/f, VVW
Figure 8.9 on page 8-11.
0.0 to 100.0 %
V/f, VVW
348 to 800 V
V/f, VVW