What it means
Alarm A35931 comes from a Terminal Module (TM): while evaluating the temperature sensor connected to channel 11, the drive found a signal it cannot use. Depending on the drive configuration, the same condition can also be output as fault F35931 or as a message without a reaction. The evaluation covers sensors of the types KTY84, PT100, PT1000 and PTC, each with its own resistance window; the alarm value in r2124 tells you which side of the window the measurement left.
Why it appears
- The drive detected an error while evaluating the temperature sensor connected to channel 11 of the Terminal Module.
- The evaluation fails when the measured resistance leaves the window valid for the connected sensor type: either the wire is broken or the sensor is not connected (resistance too high), or the measured resistance is too low.
What to check
- Read the alarm value in r2124 as a decimal number to see which case applies: 1 = wire breakage or sensor not connected, 2 = measured resistance too low.
- Make sure that the sensor is connected correctly — with alarm value 1, a broken wire or a sensor that is simply not plugged in is what you are looking for.
- If the sensor is connected correctly and the message remains, replace the sensor.
Reading the message value
- The drive writes the alarm value into r2124; interpret the value as a decimal number.
- 1 — wire breakage or sensor not connected: KTY84 with R > 2170 Ohm, PT100 with R > 194 Ohm, PT1000 with R > 1944 Ohm.
- 2 — measured resistance too low: PTC thermistor with R < 20 Ohm, KTY84 with R < 180 Ohm, PT100 with R < 60 Ohm, PT1000 with R < 603 Ohm.
Parameters the manual names
- r2124 — holds the alarm value of this message; read it as a decimal number to tell a wire break or a missing sensor (1) apart from a resistance that is too low (2).
Acknowledging and restarting
No acknowledgement is provided for the alarm: the manual assigns it neither a reaction nor an acknowledgement, so there is nothing to reset at the drive. The fix is to connect the sensor correctly or to replace it. If the drive is configured to signal the same condition as a fault instead, that fault is acknowledged IMMEDIATELY (POWER ON) — by switching the power supply off and on again.
The same on every family
Every manual that describes A35931 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | External measured value / signal state outside the permissible range (16) | Terminal Module (TM) | SINAMICS S120, S150 List Manual · p. 3248 |
| G130, G150 | NONE | NONE | External measured value / signal state outside the permissible range (16) | Terminal Module (TM) | SINAMICS G130, G150 List Manual · p. 1910 |
The drives this code lives on
A35931 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 A35931 in SINAMICS mean?
A Terminal Module has detected an error while evaluating the temperature sensor on channel 11. Usually the sensor wire is broken, the sensor is not connected, or its resistance is outside the window valid for the sensor type.
How do I fix A35931?
Make sure the temperature sensor is connected correctly and replace the sensor if the connection is fine. The alarm itself requires no acknowledgement.
Where can I see why A35931 was raised?
The drive stores the alarm value in r2124; read as a decimal number, 1 means wire breakage or sensor not connected and 2 means the measured resistance is too low.
Which resistance values trigger A35931?
A PT100 triggers it above 194 Ohm (wire break) or below 60 Ohm; KTY84 above 2170 Ohm or below 180 Ohm, PT1000 above 1944 Ohm or below 603 Ohm, and a PTC thermistor below 20 Ohm.
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 A35xxx group · SINAMICS manuals · Siemens manuals