What it means
N31800 appears with the title “Encoder 1: Group signal” on G130, G150, S120 and S150 converters. It is a message without a reaction of its own and reports that the motor encoder has detected at least one fault. Because it is a group signal, it does not name the fault itself — the accompanying messages do (one example is N31415). Depending on the drive’s configuration, the same condition can also be raised as fault F31800; in that case the drive executes the response printed in the remedy: OFF2 on the infeed, and the ENCODER response (IASC/DCBRK) on servo, vector and HLA drive objects.
Why it appears
- The motor encoder has detected at least one fault; the group signal itself carries no further detail about which fault it is.
What to check
- Go through the messages that are present at the same time: the manual’s remedy is to
Evaluate the other messages that are presently available.
Those messages name the actual encoder fault behind this group signal. - Look at the response stored in p0491 (Motor encoder fault response ENCODER), to which the cause entry refers for this message.
Parameters the manual names
- p0491 — Motor encoder fault response ENCODER: named in the cause entry for this group signal; it holds the response the drive applies to the encoder fault announced here.
Acknowledging and restarting
N31800 itself needs no acknowledgement action: as a message it only points to the other encoder messages, and those messages and their causes determine what has to be cleared. If the drive is configured to raise the same condition as fault F31800 instead, the fault is acknowledged IMMEDIATELY after the remedy, as the G130/G150 entry states.
What differs between the drive families
Straight from the manuals' own fields — N31800 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) | NONE | Actual position/speed value incorrect or not available (11) | None | SINAMICS S120, S150 List Manual · p. 3060 |
| G130, G150 | Vector: ENCODER (IASC/DCBRK, NONE) Infeed: OFF2 (NONE) | NONE | Actual position/speed value incorrect or not available (11) | None | SINAMICS G130, G150 List Manual · p. 1745 |
The drives this code lives on
N31800 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 SINAMICS code N31800 mean?
It is the message “Encoder 1: Group signal”: the motor encoder has detected at least one fault. As a group signal it does not identify the fault — the other messages active at the same time do.
How do I clear N31800 on a SINAMICS drive?
Evaluate the other messages that are presently available and clear the encoder fault they name; p0491 shows which encoder fault response is configured. As a message, N31800 itself requires no acknowledgement.
Does N31800 stop the drive?
Not as a message — it comes without a reaction. If the drive outputs the same condition as fault F31800, the infeed performs OFF2 and the servo, vector and HLA drive objects execute the ENCODER response (IASC/DCBRK).
Which SINAMICS drives use code N31800?
The manuals describe it for G130, G150, S120 and S150 converters.
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 N31xxx group · SINAMICS manuals · Siemens manuals