Siemens 420 manual Motor holding brake MHB, On / OFF1/OFF3

Issue 07/04 3 Functions

3.13Motor 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).

ON / OFF1/OFF3:
ON
OFF1/OFF3		t
Motor excitation
finished
r0056 Bit04		t
f	P0346
fmin
(P1080)
		t
	P1216	P1217
r0052.C	Point 1	Point 2
1
0		t

Fig. 3-48 Motor holding brake after ON / OFF1

MICROMASTER 420	Operating Instructions
6SE6400-5AA00-0BP0	119