What it means
F31850 reports that the evaluation software in the Sensor Module of encoder 1 has detected an internal error. The fault value stored in r0949 identifies which internal function reported the error. Depending on how the drive is configured, the same condition can also be issued as an alarm (A) or without a reaction (N).
Why it appears
- An internal software error has occurred in the Sensor Module that evaluates encoder 1.
- The fault value in r0949 (interpret decimal) shows which internal function failed — see the decoding below.
What to check
- Read the fault value in r0949 as a decimal number to identify the faulted internal function.
- Replace the Sensor Module.
- If required, upgrade the firmware in the Sensor Module.
- If the fault persists, contact Technical Support.
Reading the message value
- The drive writes the fault value into r0949; interpret it as a decimal number. The manual decodes it as follows:
- 1: Background time slice is blocked.
- 2: Checksum over the code memory is not OK.
- 10000: OEM memory of the EnDat encoder contains data that cannot be interpreted.
- 11000 ... 11499: Descriptive data from EEPROM incorrect.
- 11500 ... 11899: Calibration data from EEPROM incorrect.
- 11900 ... 11999: Configuration data from EEPROM incorrect.
- 12000 ... 12008: communication with analog/digital converter faulted.
- 16000: DRIVE-CLiQ encoder initialization application error.
- 16001: DRIVE-CLiQ encoder initialization ALU error.
- 16002: DRIVE-CLiQ encoder HISI / SISI initialization error.
- 16003: DRIVE-CLiQ encoder safety initialization error.
- 16004: DRIVE-CLiQ encoder internal system error.
Parameters the manual names
- r0949 — read here as a decimal number to determine which internal software error the Sensor Module of encoder 1 reported.
- p0491 — motor encoder fault response (ENCODER); the fault text refers to this parameter for the drive's response to the encoder fault.
Acknowledging and restarting
The fault is only acknowledged by powering the drive up again (POWER ON). When the condition is configured as an alarm (A) or without a reaction (N), the manual specifies neither a reaction nor an acknowledgement.
What differs between the drive families
Straight from the manuals' own fields — F31850 is not described identically everywhere.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | Infeed: OFF2 (NONE) Servo: ENCODER (IASC/DCBRK, NONE) Vector: ENCODER (IASC/DCBRK, NONE) Hla: ENCODER (NONE) | POWER ON | Hardware/software error (1) | Sensor Module Encoder 1 | SINAMICS S120, S150 List Manual · p. 3069 |
| G130, G150 | Vector: ENCODER (IASC/DCBRK, NONE) Infeed: OFF2 (NONE) | POWER ON | Hardware/software error (1) | Sensor Module Encoder 1 | SINAMICS G130, G150 List Manual · p. 1753 |
The drives this code lives on
F31850 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 F31850 mean on a SINAMICS drive?
An internal software error has occurred in the Sensor Module that evaluates encoder 1. The fault value in r0949, read as a decimal number, identifies the internal function that reported the error.
How is F31850 cleared and acknowledged?
The manual's remedy is to replace the Sensor Module, upgrade its firmware if required, and otherwise contact Technical Support. The fault is acknowledged only by powering the drive up again (POWER ON).
What does fault value 10000 in r0949 mean for F31850?
It means the OEM memory of the EnDat encoder contains data that cannot be interpreted. Other ranges in r0949 point to incorrect EEPROM data, converter communication faults or DRIVE-CLiQ encoder initialization errors.
Which parameter belongs to fault F31850?
p0491, the motor encoder fault response (ENCODER), is referenced in the fault text and governs how the drive responds to this encoder fault. r0949 holds the fault value that identifies the specific error.
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 F31xxx group · SINAMICS manuals · Siemens manuals