Lenze 8400 - Manual (Page 275)

Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
275
5 Motor control (MCTRL)
5.13 Braking operation/brake energy management
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5.13.2.1 Inverter motor brake
With this braking method, which can be selected as an alternative in C00175 , the regenerative
energy in the motor is converted as a result of dynamic acceleration/deceleration with down-
ramping of the ramp function generator..

Tip!
If no brake resistor is used, the DC injection brake can also be used for a braking process in
addition to the "inverter motor brake" and "Stopping of the ramp function generator".
 DC-injection braking ( 248)
In applications with high mass inertia and long braking times (> 2 s), we recommend the
use of the DC injection brake.
• The DC injection brake provides for an oscillation-minimised braking. The braking
process generally takes more time than the "inverter motor brake" function with an
optimised setting. Moreover, the function is only recommended for braking to a
standstill.
In the following cases we recommend the "inverter motor brake" function:
• With servo control (SC).
• For all applications that do not require braking to a standstill (e.g.braking to a lower
speed setpoint) or the braking process can be interrupted by selecting a new speed
setpoint.
• For applications with low mass inertias and a short braking time (< 1 s).
• For all applications where braking should be as quick as possible.

Stop!
• This braking method only works without intervention of a position controller in the
case of speed-controlled applications!
• When the "inverter motor brake" function is used, the Motor load monitoring (I2xt) is
not adapted. If it is braked too frequently, there is a risk of the motor being thermally
overloaded or the motor overload monitoring does not work properly!
• The "inverter motor brake" function must not be used with vertical conveyors (hoists)
or with active loads!