Lenze 8400 - Manual (Page 250)

5 Motor control (MCTRL)
5.10 Parameterisable additional functions
250
Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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C. When the controller is enabled, the motor (still) rotates at a speed which is above the auto DCB
threshold. If the speed setpoint reached via the acceleration ramp exceeds the auto DCB
threshold ( C00019 ), the motor will be energised and the following action will take place:
• During operation without speed feedback, the drive is "caught".
 Flying restart function ( 245)
• During operation with speed feedback, the drive synchronises to the current actual speed
value.

Tip!
We recommend to deactivate the auto DCB function during operation with speed feedback
via a setting of C00019 = 0.
Auto DCB function during operation with speed feedback
If you want to use the auto DCB function contrary to our recommendation (see above), the auto DCB
threshold must not fall below the following values depending on the number of encoder
increments ( C00420 ):

How to set the automatic DC-injection braking
1. Set a hold time in C00106 > 0 s.
• Automatic DC-injection braking is active for the time set.
• In case of operation without speed feedback, the braking current set in
C00036 is
injected.
• After the set hold time has expired, the controller sets a pulse inhibit.
2. Set the operating threshold in C00019 .
• The operating threshold can serve to set a dead band in the setpoint. If DC-injection
braking is not to be active then, C00106 must be set to a value of "0".

Stop!
If the DC-injection braking operation is too long and the braking current or braking
voltage is too high, the connected motor may overheat.
Number of encoder increments
C00420
Auto DCB threshold C00019
8 16
16 8
32 4
64 2
> 128 No restrictions