Lenze 8400 - Manual (Page 249)

Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
249
5 Motor control (MCTRL)
5.10 Parameterisable additional functions
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5.10.3.1 Manual DC-injection braking (DCB)
DC-injection braking can be activated manually for the two technology applications "Actuating
drive speed" and "Switch-off positioning" by connecting the bSetDCBrake input of the LA_NCtrl or
LA_SwitchPos application block to a digital signal source (e.g. via the digital signal source bCtrl1_B3
of the port block LP_CANIn1).
• For HIGH-active inputs, DC-injection braking is active as long as the signal is at HIGH level.
• After the hold time (
C00107 ) has expired, the controller sets the pulse inhibit.
5.10.3.2 Automatic DC-injection braking (Auto-DCB)
"Automatic DC-injection braking" (referred to in the following as "auto DCB") can be used if there is
a requirement that the drive be isolated from the supply at n
≈ 0.
Function
For understanding the auto DCB function, it is necessary to distinguish between three different
types of operation:
A. The drive has been enabled and, in the course of operation, the speed setpoint falls below the
auto DCB threshold.
• In case of operation without speed feedback, a braking current ( C00036 ) is injected. After the
auto DCB hold time ( C00106 ) has expired, the motor is deenergised via the auto DCB
function, i.e. a controller inhibit (CINH) is set.
• In case of operation with speed feedback, the motor is deenergised via the auto DCB function
after the auto DCB hold time ( C00106 ) has expired, i.e. a controller inhibit (CINH) is set.
The braking current which can be parameterised in C00036 does not have any effect during
operation with speed feedback.
B. When the controller is enabled, the drive is at standstill (n = 0).
If the enabled drive is to start, the speed setpoint passed via the acceleration ramp must exceed
the auto DCB threshold ( C00019 ). Below this threshold, the motor will not be energised.

Note!
Deactivate automatic DC-injection braking when a holding brake is used!
• For this purpose, go to C00019 and set the auto DCB threshold to "0".
• Background: Controller inhibit is already activated by the Holding brake control .
( 535)