What it means
A01794 is raised by the Control Unit (CU) when the modulo value set for the SI Motion safe position via PROFIsafe (p9505) does not fit into the range the drive can represent: the position actual value can then jump when that range overflows. Depending on the drive's configuration, the same condition can also be reported with no reaction (N).
Why it appears
- The modulo value for the safe position via PROFIsafe (p9505) is parameterized so that the position actual value can jump when the range that can be represented overflows.
- The range that can be represented is +/- 2048 revolutions for the 32-bit value and +/- 2048 revolutions for the 16-bit value; which of the two applies depends on p9574.
What to check
- Check the modulo value set in p9505 against the representable range of +/- 2048 revolutions: can an overflow with a jump of the position actual value occur?
- Correct the parameter assignment: set p9505 to 2^n revolutions and to complete revolutions, i.e. a multiple of 360°.
Parameters the manual names
- p9505 — SI Motion SP modulo value (Control Unit): the modulo value for the safe position; set it to 2^n revolutions and to complete revolutions (a multiple of 360°).
- p9574 — SI Motion safe position scaling (Control Unit): the representable range for the 16-bit value depends on this setting.
- p2118 — message number used, together with p2119, to re-parameterize this alarm to "NO REPORT".
- p2119 — message type used, together with p2118, to re-parameterize this alarm to "NO REPORT".
Acknowledging and restarting
If the possible position actual value jump can be tolerated for the particular application — for example because the parameterized modulo range fits "almost as integer number" into the representable +/- 2048 revolutions — the alarm can be hidden by re-parameterizing it to "NO REPORT". To re-parameterize the alarm to "NO REPORT", it is not permissible that the alarm is present.
The manual therefore requires this sequence: correct p9505 to "2^n", re-parameterize the alarm using p2118 and p2119, then set p9505 back to the required value.
The same on every family
Every manual that describes A01794 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| G130, G150 | NONE | NONE | Hardware/software error (1) | Control Unit (CU) | SINAMICS G130, G150 List Manual · p. 1485 |
| S120, S150 | NONE | NONE | Hardware/software error (1) | Control Unit (CU) | SINAMICS S120, S150 List Manual · p. 2705 |
The drives this code lives on
A01794 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 alarm A01794 in SINAMICS mean?
It reports that the modulo value for the SI Motion safe position via PROFIsafe (p9505) allows the position actual value to jump when the representable range of +/- 2048 revolutions overflows.
How do I fix A01794?
Correct the parameter assignment of p9505: set it to 2^n revolutions and to complete revolutions, i.e. a multiple of 360°.
Can alarm A01794 be suppressed?
Yes, if the possible position actual value jump is tolerable for the application. The alarm must not be present while you re-parameterize it, so first set p9505 to "2^n", then change the message type with p2118 and p2119, and finally restore p9505.
Which parameters belong to the safe position modulo range?
p9505 holds the SI Motion safe position modulo value on the Control Unit; the representable range for the 16-bit value depends on the scaling parameter p9574.
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