3  Functions  Issue 10/06 
  MICROMASTER 440      Operating Instructions 
206  6SE6400-5AW00-0BP0 
WARNING 
¾  For compound braking, regenerative braking is superimposed on the DC 
braking (braking along a ramp). This means that components of the kinetic 
energy of the motor and driven load are converted into thermal energy in the 
motor. If this power loss is too high or if the braking operation takes too long, 
then this can cause the drive to overheat ! 
¾  When using compound braking it must be expected that there is a higher level 
of noise above the compound braking switch-in threshold. 
NOTE 
¾  Only active in conjunction with V/f control.  
¾  Compound braking is de-activated, if 
-  flying restart is active, 
-  DC braking is active, and  
-  Vector control (SLVC, VC) is selected. 
¾  The compound switch-in threshold V
DC-Comp
 is dependent on P1254  
  V
DC-Comp
(P1254 = 0)  ≠  V
DC-Comp
(P1254 ≠ 0)  
a)  Auto-detect circuit enabled (P1254 = 1): 
- V
DC-Comp 
(P1254 = 1) is automatically calculated when the drive inverter 
runs-up - i.e. after the line supply voltage has been connected 
-  Using the auto-detect function, the V
DC-Comp 
threshold automatically 
adapts itself to the line supply voltage at the particular installation 
location. 
b)  Auto-detect function disabled (P1254 = 0): 
- 
0210P213.1U Comp,DC ⋅⋅=  
- The V
DC-Comp 
threshold is immediately re-calculated after entering P0210  
-  P0210 must be adapted to the particular installation location 
 
 
3.15.3 Dynamic braking 
Parameter range:  P1237 
Warnings A0535 
Faults F0022 
Function chart number:  - 
For several drive applications, in certain operating states, the motor can 
regenerate. Examples of these applications include: 
¾ Cranes 
¾ Traction drives 
¾  Conveyor belts which transport loads downwards 
When the motor is in the regenerative mode, the energy from the motor is fed back 
into the DC link of the drive converter via the inverter. This means that the DC link 
voltage increases and when the maximum threshold is reached, the drive inverter 
is shutdown (tripped) with fault F0002. This shutdown (trip) can be avoided by 
using dynamic braking. Contrary to DC and compound braking, this technique 
requires that an external braking resistor is installed.