What it means
A07931 carries the message text Brake does not open
and belongs to the motor holding brake function. The drive outputs this alarm when bit 4 of the motor holding brake status word is set (r1229.4 = 1); alongside the status word r1229, the alarm's cause text also refers to the motor holding brake opening time p1216. Depending on how the drive is configured, the same condition can also be output as a fault or as a message without any reaction.
Why it appears
- The alarm is output for r1229.4 = 1, i.e. while bit 4 of the motor holding brake status word r1229 is set; per the message text, the motor holding brake does not open.
What to check
- Check the functionality of the motor holding brake.
- Check the feedback signal that reports the brake as open; the source of this signal is selected in p1223 (BI: Motor holding brake feedback signal brake open).
Parameters the manual names
- r1229 — motor holding brake status word: read bit 4 here; the alarm is output while this bit is set.
- p1216 — motor holding brake opening time (Brake t_open): the brake opening time to which the alarm's cause text refers together with r1229.
- p1223 — BI: Motor holding brake feedback signal brake open (Brake feedb open): the signal that reports the brake as open; check the source selected here.
Acknowledging and restarting
As an alarm, A07931 requires no acknowledgment; it is present while r1229.4 = 1 and ends when bit 4 of r1229 returns to 0. If the drive is configured to output the same condition as a fault instead, it triggers no automatic drive reaction and can be acknowledged immediately; as a message without reaction it likewise requires no acknowledgment.
The same on every family
Every manual that describes A07931 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| G130, G150 | NONE | NONE | Application/technological function faulted (17) | Motor | SINAMICS G130, G150 List Manual · p. 1614 |
| S120, S150 | NONE | NONE | Application/technological function faulted (17) | Motor | SINAMICS S120, S150 List Manual · p. 2885 |
The drives this code lives on
A07931 is described for G130, G150, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does the SINAMICS alarm A07931 Brake does not open mean?
It is an alarm from the motor holding brake function. The drive outputs it when bit 4 of the motor holding brake status word r1229 is set (r1229.4 = 1).
How do I clear A07931?
Check the functionality of the motor holding brake and check the brake-open feedback signal selected in p1223. The alarm needs no acknowledgment and ends once r1229.4 returns to 0.
Which parameters belong to A07931?
r1229 (motor holding brake status word), p1216 (motor holding brake opening time) and p1223 (BI: motor holding brake feedback signal brake open).
Is A07931 an alarm or a fault?
It is output as an alarm, but depending on the drive configuration the same condition can also appear as a fault or as a message without any reaction. As a fault it triggers no automatic drive reaction and can be acknowledged immediately.
Codes next to this one
Source
Written from Siemens' own List Manuals and operating instructions; every number, designation and parameter on this page is checked against them before publication.
All SINAMICS codes: fault and alarm codes · the A07xxx group · SINAMICS manuals · Siemens manuals