What it means
This alarm is raised when the COB-ID of a CAN PDO was not set invalid before the mapping was changed. For online operation, the appropriate COB-ID must be set invalid before mapping; if that order is not kept, the drive issues A08757. The manual demonstrates the procedure on RPDO 1, with the COB-ID held in p8700[0] and the mapping in p8710[0].
Why it appears
- The mapping of a receive PDO was changed in online operation while its COB-ID was still valid, instead of being set invalid first.
- The sequence the manual prescribes was not followed: first set the COB-ID invalid (p8700[0] = C00006E0 hex), then change the mapping (p8710[0]), then enter a valid COB-ID again in p8700[0].
What to check
- Set the COB-ID of the affected PDO invalid — for RPDO 1:
set p8700[0] = C00006E0 hex (invalid COB-ID)
. - Then set the mapping as required — for RPDO 1:
set p8710[0] as required
. - Finish with
p8700[0] enter a valid COB-ID
. - Apply the same order to whichever receive PDO mapping you are changing; RPDO 1 is only the manual's example.
Parameters the manual names
- p8700 (CAN Receive PDO 1): carries the COB-ID of receive PDO 1 — for this alarm it is first given the invalid value C00006E0 hex and afterwards a valid COB-ID again.
- p8710 (CAN Receive Mapping for RPDO 1): the mapping that is set as required while the COB-ID is invalid.
Acknowledging and restarting
The alarm is resolved by working through the steps above in the given order. The drive does not trip on it, and once a valid COB-ID has been entered again in p8700[0], no further acknowledgement step is needed.
What differs between the drive families
Straight from the manuals' own fields — A08757 is not described identically everywhere.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Error in the parameterization / configuration / commissioning procedure (18) | None | SINAMICS S120, S150 List Manual · p. 2929 |
| G130, G150 | NONE | NONE | Error in the parameterization / configuration / commissioning procedure (18) | None | SINAMICS G130, G150 List Manual · p. 1643 |
| G120 | NONE | NONE | Error in the parameterization / configuration / commissioning procedure (18) | — | SINAMICS G120 · p. 902 |
The drives this code lives on
A08757 is described for G120, G130, G150, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does alarm A08757 mean on a SINAMICS drive?
It reports that, during online operation, a CAN COB-ID was not set invalid before the PDO mapping was changed. The drive expects the order: COB-ID invalid, then mapping, then a valid COB-ID again.
How do I clear A08757?
Set the COB-ID of the affected PDO invalid (for RPDO 1: p8700[0] = C00006E0 hex), then set the mapping (p8710[0]) as required, and finally enter a valid COB-ID in p8700[0].
Which parameters belong to A08757?
p8700 holds the COB-ID of receive PDO 1 and p8710 holds the receive mapping for RPDO 1. The alarm appears when p8710 is changed while p8700 still carries a valid COB-ID.
Does A08757 stop the drive?
No. The drive does not trip on this alarm, and after the sequence has been carried out with a valid COB-ID, no acknowledgement is required.
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 A08xxx group · SINAMICS manuals · Siemens manuals