Code 20002: [Channel %1: ] Axis %2 zero mark not found
Problembeschreibung & Sicherheitswarnung
Die Siemens SINUMERIK 840D CNC hat einen kritischen [Channel %1: ] Axis %2 zero mark not found-Alarm ausgelöst. Sofortige Aufmerksamkeit durch einen qualifizierten Bediener oder Wartungstechniker ist erforderlich, um Folgeschäden an der Ausrüstung oder verdorbene Teile während des Fertigungszyklus zu vermeiden. Stellen Sie immer sicher, dass standardmäßige Sicherheits- und LOTO-Verfahren befolgt werden, bevor Sie auf Schaltschränke zugreifen.
Offizielle Schritte zur Fehlerbehebung
Parameters: %1 = Channel number %2 = Axis name, spindle number Definitions: The hardware zero mark of the incremental position encoder or the substitute zero mark of the absolute position encoder is not within a defined section. Phase 2 of the reference point approach ends when th e zero mark of the encoder has been detected after the rising/falling edge of the NC/PLC interfac e signal DB31,... DBX12.7 (Deceleration reference point approach) has given the trigger start. The maximum distance between the trigger start and the zero mark that follows is defined in the MD34060 $MA_REFP_MAX_MARKER_DIST. The monitor prevents a zero mark signal from being overtraveled and the nex t being evaluated as reference point signal. (Faulty cam adjustment or excessive delay by the PLC user program). Reaction: NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm. Remedy: Please inform the authorized personnel/service department. Check the cam adjustment and make sure that the distance is sufficient between the end of the cam and the zero marker signal that follows. The path must be greater than the axis can cover in the PLC cycle time. Increase the MD34060 $MA_REFP_MAX_MARKER_DIST, but do not select a value greater than the distance between the 2 zero markers. This might result in the monitor being switched off. Program Continuation: Clear alarm with the RESET key. Restart part program
Source: SINUMERIK 840D sl / 840Di sl / SINAMICS S120 Diagnostics Manual (DAsl, 03/2009)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
Über Siemens SINUMERIK 840D CNC Alarme
Industriesteuerungen von Siemens verfügen über umfangreiche Diagnosesysteme zum Schutz der internen Schaltkreise und mechanischen Verbindungen. Wenn eine SINUMERIK 840D CNC einen Fehlercode wie 20002 ausgibt, deutet dies typischerweise auf eine Diskrepanz zwischen befohlenen Werten und tatsächlichem Sensor-Feedback hin.
Vollständige Alarmliste: 4014 Siemens SINUMERIK 840D CNC codes.
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