What it means
A33400 is the Encoder 3 message for zero mark monitoring: the measured zero mark distance does not correspond to the parameterized zero mark distance, so the alarm threshold is exceeded. The threshold is the zero mark distance set in p0425 (rotary encoder) or p0424 (linear encoder). For distance-coded encoders the zero mark distance is formed from pairs of detected zero marks; depending on how the pairs are generated, an individual missing zero mark therefore does not necessarily raise a message and has no effect in the system. The manuals print the code as Encoder 3: Zero mark distance error (alarm threshold exceeded)
and Encoder 3: Alarm threshold zero mark distance error
. Depending on how the drive is configured, the same condition can also be issued as a fault (F) or as a message without reaction (N).
Why it appears
- The measured zero mark distance does not correspond to the parameterized zero mark distance; monitoring compares the measurement against the value set in p0425 (rotary encoder) or p0424 (linear encoder).
- For distance-coded encoders the zero mark distance is determined from detected pairs of zero marks, so depending on the pair generation a missing zero mark does not necessarily produce a message.
What to check
- Check that the encoder cables are routed in compliance with EMC.
- Check the plug connections.
- Check the encoder type — the encoder must have equidistant zero marks.
- Adapt the parameter for the distance between zero marks (p0424, p0425).
- Replace the encoder or the encoder cable.
Reading the message value
- The message value is the alarm value in r2124; read it and interpret it as a decimal number.
- It contains the last measured zero mark distance in increments — 4 increments equal 1 encoder pulse.
- The sign designates the direction of motion when the zero mark distance was detected.
Parameters the manual names
- p0425 — zero mark distance of the rotary encoder; the value the zero mark monitoring compares against, and the parameter to adapt when Encoder 3 is rotary.
- p0424 — zero mark distance of the linear encoder; the parameter to adapt when Encoder 3 is linear.
- r2124 — alarm value; read the last measured zero mark distance here, interpreted as a decimal number.
Acknowledging and restarting
As an alarm, A33400 requires no acknowledgement and no automatic reaction follows it. If the drive configuration outputs the same condition as a fault (F), it must be acknowledged immediately (IMMEDIATELY); the without-reaction output (N) likewise requires no acknowledgement.
The same on every family
Every manual that describes A33400 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Actual position/speed value incorrect or not available (11) | Encoder 3 | SINAMICS S120, S150 List Manual · p. 3152 |
| G130, G150 | NONE | NONE | Actual position/speed value incorrect or not available (11) | Encoder 3 | SINAMICS G130, G150 List Manual · p. 1824 |
The drives this code lives on
A33400 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 A33400 mean on a SINAMICS drive?
The distance between zero marks measured at Encoder 3 deviates from the zero mark distance set for monitoring, so the alarm threshold is exceeded. The threshold is held in p0425 for a rotary encoder or p0424 for a linear encoder.
How do I acknowledge or reset A33400?
As an alarm it requires no acknowledgement and no automatic reaction follows. If the drive is configured to raise the same condition as a fault (F), it must be acknowledged immediately.
Where do I see the measured zero mark distance for A33400?
In r2124, read as a decimal alarm value: it holds the last measured zero mark distance in increments, with 4 increments equal to 1 encoder pulse. The sign shows the direction of motion during detection.
Which parameters should I check for A33400?
p0424 and p0425, which set the distance between zero marks for a linear and a rotary encoder respectively. The remedy lists adapting these parameters, and replacing the encoder or encoder cable as the last step.
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