What it means
A33940 is the message the drive raises for Encoder 3 when the voltage of the analog spindle sensor S1 leaves the permissible range. That range follows from the spindle voltage thresholds (p5041) together with their tolerance (p5040). The signal level the drive measured at sensor S1 is stored in r2124 and can be read there. Depending on how the drive is configured, the same condition can also be output as a fault (F) or with no reaction (N) instead of the alarm.
Why it appears
- The voltage of the analog spindle sensor S1 is outside the permissible range.
What to check
- Check the tool that is clamped in the spindle.
- Check the tolerance and, if required, adapt it (p5040, spindle voltage threshold values tolerance).
- Check the thresholds and, if required, adapt them (p5041, spindle voltage threshold values).
- Check analog sensor S1 and its connections.
Reading the message value
- The drive places the alarm value in r2124; the message value (%1) carries this value.
- Interpret r2124 as a decimal number — it is the signal level from sensor S1.
A signal level of 500 mV corresponds to the numerical value 500 dec.
Parameters the manual names
- r2124 — alarm value: read the signal level from sensor S1 here, interpreting the value as a decimal number.
- p5040 — spindle voltage threshold values tolerance: check this tolerance and adapt it if required.
- p5041 — spindle voltage threshold values: check these thresholds and adapt them if required so that they match the voltage actually delivered by sensor S1.
Acknowledging and restarting
The alarm requires no acknowledgement and goes away once the voltage of sensor S1 is back inside the permissible range. The drive takes no automatic action on this condition, so it does not change its operating state by itself. If the condition is configured as a fault, it must be acknowledged IMMEDIATELY.
The same on every family
Every manual that describes A33940 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Application/technological function faulted (17) | Encoder 3 | SINAMICS S120, S150 List Manual · p. 3181 |
| G130, G150 | NONE | NONE | Application/technological function faulted (17) | Encoder 3 | SINAMICS G130, G150 List Manual · p. 1851 |
The drives this code lives on
A33940 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 A33940 mean on a SINAMICS drive?
The voltage of the analog spindle sensor S1 at Encoder 3 is outside the permissible range. The measured signal level is stored in r2124 and is read as a decimal number — 500 dec corresponds to 500 mV.
How do I fix alarm A33940?
Check the clamped tool, then check and if required adapt the tolerance in p5040 and the thresholds in p5041, and finally check analog sensor S1 and its connections. The alarm needs no acknowledgement and disappears once the voltage is back in range.
Does A33940 stop the drive?
No — the drive takes no automatic action, neither as alarm nor as fault. If the condition is configured as a fault, acknowledge it IMMEDIATELY.
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 A33xxx group · SINAMICS manuals · Siemens manuals