Issue 07/04  3  Functions 
MICROMASTER 420    Operating Instructions   
6SE6400-5AA00-0BP0 
119 
3.13  Motor holding brake (MHB)  
Parameter range:  P1215 
  P0346, P1216, P1217, P1080 
  r0052 bit 12 
Warnings - 
Faults -  
Function chart number:  - 
For drives which must be secured when powered-down to prevent them 
undesirably moving, the MICROMASTER brake sequence control (enabled via 
P1215) can be used to control the motor holding brake.  
Before opening the brake, the pulse inhibit must be removed and a current 
impressed which keeps the drive in that particular position. In this case, the 
impressed current is defined by the min. frequency P1080. A typical value in this 
case is the rated motor slip r0330. In order to protect the motor holding brake from 
continuous damage, the motor may only continue to move after the brake has been 
released (brake release times lie between 35 ms and 500 ms). This delay must be 
taken into account in parameter P1216 "Holding brake release delay" (refer to Fig. 
3-48). 
0
t
fmin
(P1080)
P1217P1216
OFF1/OFF3
ON
t
ON / OFF1/OFF3:
1
r0052.C
t
f
Point 2Point 1
t
P0346
Motor excitation
finished
r0056 Bit04
Fig. 3-48  Motor holding brake after ON / OFF1