User guide

Table Of Contents
Lenze · 8400 BaseLine C · Reference manual · DMS 1.6 EN · 01/2014 · TD05 97
5 Motor control (MCTRL)
5.6 Parameterisable additional functions
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5.6.3.1 Manual DC-injection braking (DCB)
DC-injection braking can be manually activated via the bSetDCBrake process input.
For HIGH-active inputs, DC-injection braking is active as long as the signal is at HIGH level.
•After the hold time ((C107
) has expired, the controller sets the pulse inhibit (CINH).
Tip!
In the preset "Terminals 0" control mode, DC-injection braking can be manually activa-
ted via the digital input DI3.
In the preset "Terminals 11" control mode, DC-injection braking can be manually activa-
ted via the digital input DI2.
5.6.3.2 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 ty-
pes 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 (C036) is injected. After the
auto-DCB hold time (C106
) has expired, the motor is deenergised via the auto-DCB function,
i.e. a controller inhibit (CINH) is set.
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 (C019
). Below this threshold, the motor will not be energised.
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 thres-
hold C019
), the motor will be energised and the drive will be "caught". Flying restart function
( 94)
How to set the automatic DC-injection braking
1. Set a hold time in C106
>0s.
Automatic DC-injection braking is active for the time set.
In case of operation without speed feedback, the braking current set in C036
is injected
After the set hold time has expired, the controller sets a pulse inhibit.
2. Set the operating threshold in C019
.
The operating threshold can serve to set a dead band in the setpoint. If DC-injection bra-
king is not to be active then, C106
must be set to a value of "0".