What it means
A01979 is an alarm of the CBExx communication board on SINAMICS S120 and S150 converters. It signals an internal error in the cyclic data transfer: the cyclic actual values and/or setpoints were not transferred within the specified times. The alarm value belonging to this message is stored in r2124.
Why it appears
- The cyclic actual values and/or setpoints did not arrive within the specified times, so the internal cyclic data transfer failed.
What to check
- Set the times T_io_input or T_io_output correctly, so that the cyclic actual values and setpoints are again transferred within the specified times.
Reading the message value
- The drive stores the alarm value in r2124, to be interpreted hexadecimal. The manual marks this value as
Only for internal Siemens troubleshooting
, so no further decoding of the message value is printed.
Parameters the manual names
- r2124 — alarm value: read it (hexadecimal) when diagnosing A01979; the manual states it is only for internal Siemens troubleshooting.
Acknowledging and restarting
No acknowledgment is required for this alarm. After T_io_input or T_io_output has been set correctly, the alarm is removed once the cyclic data is again transferred within the specified times.
The same on every family
Every manual that describes A01979 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Communication error to the higher-level control system (9) | None | SINAMICS S120, S150 List Manual · p. 2722 |
The drives this code lives on
A01979 is described for S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does alarm A01979 mean on SINAMICS S120 or S150?
The CBExx communication board reports an internal error for cyclic data transfer: the cyclic actual values and/or setpoints were not transferred within the specified times.
How do I clear alarm A01979?
Correctly set T_io_input or T_io_output, as the manual's remedy states. No acknowledgment is required for this alarm.
What does the alarm value of A01979 in r2124 tell me?
It must be interpreted hexadecimal. The manual states the value is only for internal Siemens troubleshooting, so there is no decoding for the field technician.
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 A01xxx group · SINAMICS manuals · Siemens manuals