Keba CDF3000, Руководство по эксплуатации

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3-18
Operating Instructions CDF3000
3 Installation
3.9 Braking resis-
tor (RB)
Attention: Braking of the drive is of importance for the safety of
machine or plant!
The safe function of the braking facility must be tested during
commissioning! In case of incorrect dimensioning (overload-
ing) the braking resistor or the brake electronics may be
destroyed and machine or plant may be damaged. Such
overload (failure of the braking facility) may even cause fatal
accidents or severe injury, e.g. in case of lifting applications!
In regenerative operation, e. g. when braking the drive, the motor feeds
energy back to the positioning controller. 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 means of a braking resistor.
The switching transistor is installed as standard. The design of the exter-
nal braking resistor depends on various factors of the drive: e. g. the load
to be moved, the required dynamics of the drive or the duration of braking
and duty cycles.
Fig. 3.11 Connection braking resistor
Please note:
• The design of the braking resistor must be clarified at the project
planning stage.
• The minimum permissible ohmic resistance of an externally
installed braking resistor for the various positioning controllers can
be found in appendix A2.
For further information please consult your project engineer.
The RB+ and RB-
terminals are not short-
circuit proof or overload-
proof.
X1
R
B
+
PE
PE
GND
L+
RB
R
B
-