D CDA3000 Inverter Drive System 750 W - 132 kW - Igor Chudov

3.7 Braking resistor
(RB)
CDA3000 Operation Manual
3 Installation
In regenerative operation, e.g. braking the drive, the motor feeds energy
back into the inverter. This increases the voltage in the DC-link. If the
voltage exceeds a threshold value, the internal braking transistor is
activated and the regenerated power is converted into heat by way of a
braking resistor.
The switching transistor is installed as standard. The design of the
external braking resistor depends on a number of drive factors:
for example the load to be moved, the required dynamics of the drive or
the braking and cycle duration.
L+
RB
X1
Figure 3.6 Braking resistor connection
Note the following points:
The design of the braking resistor must be clarified at the project
planning stage.
For details of the permissible minimum ohmic resistance of an
externally installed braking resistor for the individual inverter
modules refer to Appendix A.2.
Details of the peak braking power with an internal braking resistor
(only with version CDA34 ...,Wx.x,BR) are also given in Appendix
A.2.
For further information please consult your project engineer.
Attention: In device version CDA3X.xxx, Wx.x, BR
the braking resistor is built-in. No additional braking resistor
may be connected to terminals X1/L+ and RB; this would
damage the inverter module.
Attention: At warning message „excessive temperature at inverter heat
sink“ the connected device must be separated from the
mains, because an overvoltage of the mains leads to an
overload of the braking resistor. Please integrate one of the
digital outputs into your control concept, e.g. set OSDxx to
WOTI (Warning heat sink temperature of device).
3-12
RB