5motor control (mctrl) – Lenze 8400 motec User Manual
Page 152
5
Motor control (MCTRL)
5.10
Parameterisable additional functions
152
Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05
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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 (
) is injected. After the
auto DCB hold time (
) 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 (
). Below this threshold, the motor will not be energised.
•
Behaviour from version 05.00.00 onwards:
The drive starts too if the speed setpoint is below
the auto DCB threshold (
). However, there will be no DC-injection braking (while
stopping).
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 (
), the motor will be energised and the drive will be "caught".
How to set the automatic DC-injection braking:
> 0 s.
• Automatic DC-injection braking is active for the time set.
• In case of operation without speed feedback, the braking current set in
injected.
• After the set hold time has expired, the controller sets a pulse inhibit.
2. Set the operating threshold in
.
• The operating threshold can serve to set a dead band in the setpoint. If DC-injection
braking is not to be active then,
must be set to a value of "0".