What it means
F01056 is printed by the manuals as CU: Internal error (clock cycle of parameter group already assigned differently)
. It is an internal error of the Control Unit (CU): the parameter group that was requested (for example IREG or NREG) is already being used in a different clock cycle. The S120/S150 and G130/G150 manuals describe the message identically, and both state that it exists only for internal Siemens troubleshooting — it is not a condition you are expected to resolve at the drive.
Why it appears
- The requested parameter group (IREG, NREG, ...) is already being used in a different clock cycle.
- The manuals give no further causes: both entries state that the message is only for internal Siemens troubleshooting.
What to check
- Read the fault value in r0949 and interpret it hexadecimal — it contains the Method ID.
- Contact Technical Support and quote that Method ID; the manuals give no other remedy for this fault.
Reading the message value
- The drive stores the Method ID in the fault value, which you read in r0949; the manual specifies interpreting the value hexadecimal. This is the value Technical Support needs.
Parameters the manual names
- r0949 (fault value) — read it out for this fault: interpreted hexadecimal it holds the Method ID that Technical Support will ask for.
Acknowledging and restarting
The drive takes no automatic reaction to this fault; the message is cleared by acknowledging it, and the manual specifies immediate acknowledgment. Acknowledging removes the message, but since the cause is internal to the Control Unit it is not the remedy the manuals give — they point to Technical Support, quoting the Method ID from r0949.
What differs between the drive families
Straight from the manuals' own fields — F01056 is not described identically everywhere.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | — | — | Hardware/software error (1) | Control Unit (CU) | SINAMICS S120, S150 List Manual · p. 2571 |
| G130, G150 | NONE | IMMEDIATELY | Hardware/software error (1) | Control Unit (CU) | SINAMICS G130, G150 List Manual · p. 1384 |
The drives this code lives on
F01056 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 fault F01056 mean on a SINAMICS drive?
It is an internal error of the Control Unit: the requested parameter group (IREG, NREG, ...) is already being used in a different clock cycle. The manuals for S120/S150 and G130/G150 describe it identically and state it is only for internal Siemens troubleshooting.
How do I reset or acknowledge F01056?
The drive takes no automatic reaction, and the manual specifies immediate acknowledgment to clear the message. Clearing the message is not the cure: the remedy given is to contact Technical Support.
Where do I find the fault value of F01056?
The drive writes the Method ID into the fault value, which you read in r0949 and interpret hexadecimal. Technical Support will ask for this value.
Can I fix F01056 myself at the drive?
No measure at the drive is described — the manuals give contacting Technical Support as the only remedy. Quote the Method ID from r0949 when you call.
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 F01xxx group · SINAMICS manuals · Siemens manuals