What it means
With A01788 the drive reports that the automatic test stop (the forced checking procedure) could not be carried out after powering up. The alarm is waiting: Safe Torque Off (STO) is still selected via the safe motion monitoring functions, or a safety message that resulted in an STO is present. The automatic test stop is performed after removing the cause.
Why it appears
- The STO function is selected via the safe motion monitoring functions.
- A safety message is present that resulted in an STO.
What to check
- Deselect STO via the safe motion monitoring functions.
- Remove the cause of the safety messages and acknowledge the messages.
Acknowledging and restarting
This alarm does not itself require an acknowledgement. Deselect STO via the safe motion monitoring functions, then remove the cause of the safety messages and acknowledge those messages. Once the cause has been removed, the drive carries out the automatic test stop and the waiting state ends.
What differs between the drive families
Straight from the manuals' own fields — A01788 is not described identically everywhere.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Safety monitoring channel has identified an error (10) | Control Unit (CU) | SINAMICS S120, S150 List Manual · p. 2705 |
| G130, G150 | NONE | NONE | Safety monitoring channel has identified an error (10) | Control Unit (CU) | SINAMICS G130, G150 List Manual · p. 1484 |
| G120 | NONE | NONE | Safety monitoring channel has identified an error (10) | — | SINAMICS G120 · p. 859 |
The drives this code lives on
A01788 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 A01788 mean on a SINAMICS drive?
After powering up, the drive could not carry out the automatic test stop (forced checking procedure) because STO (Safe Torque Off) is selected via the safe motion monitoring functions, or because a safety message that resulted in an STO is present.
How do I clear A01788?
Deselect STO via the safe motion monitoring functions, then remove the cause of the safety messages and acknowledge the messages. The automatic test stop is performed after the cause has been removed.
Does A01788 have to be acknowledged?
No, the alarm itself requires no acknowledgement. Only the safety messages behind the STO must be acknowledged as part of the remedy.
What is STO in alarm A01788?
STO stands for Safe Torque Off. Here it means STO is active through the safe motion monitoring functions or through a safety message, which is why the automatic test stop cannot run yet.
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