Lenze 8400 - Manual (Page 248)

5 Motor control (MCTRL)
5.10 Parameterisable additional functions
248
Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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5.10.3 DC-injection braking
DC-injection braking allows the drive to be quickly braked to a standstill without the need to use an
external brake resistor.
• The braking current is set in C00036 .
• The maximum braking torque to be generated by the DC braking current is approx. 20 ... 30 %
of the rated motor torque. It is lower than that for braking in generator mode with an external
brake resistor.
• Automatic DC-injection braking (auto DCB) improves the starting performance of the motor
when operated without speed feedback.

Tip!
DC-injection braking has the advantage that it is possible to influence the braking time by
changing the motor current or the braking torque..
Short overview of the relevant parameters:
Procedure
DC-injection braking can be carried out in two ways with different types of activation:
 Manual DC-injection braking (DCB) ( 249)
 Automatic DC-injection braking (Auto-DCB) ( 249)

Danger!
The DC-injection braking or auto DC-injection braking function cannot be used with
sensorless control for synchronous motors (SLPSM) and servo control (SC) mode.
Holding braking is not possible when this braking mode is used!
• For low-wear control of a holding brake, use the basic function " Holding brake
control ". ( 535)
Parameter Info Lenze setting
Value Unit
C00019 Auto-DCB: Threshold
• Operating threshold for activating DC-injection
braking
3 rpm
C00036 DC braking: Current
• Braking current in [%] based on rated device
current ( C00098 )
50 %
C00106 Auto-DCB: Hold time 0.500 s
C00107 DC braking: Hold time 999.000 s
C00701/4 LA_NCtrl: bSetDCBrake
• Selection of the signal source for activating DC-
injection braking
Dependent on the selected
control mode