Code 2101: NCK battery alarm
Problembeschreibung & Sicherheitswarnung
Die Siemens SINUMERIK 840D CNC hat einen kritischen NCK battery alarm-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
Definitions: The undervoltage monitoring (2.4 - 2.6 V) of the NCK battery has responded during cyclic operation. Reaction: Alarm display. Remedy: If the NCK battery is replaced without interrupting the power supply, no data will be lost. This means that production can continue without taking any furt her steps. (A buffer capacitor on the NCK holds the supply voltage for at least 30 minutes and the batte ry can be replaced within this time even when the control is switched off). Sinumerik combines an NCU's two potential parts s ubject to wear (fan/battery) in one shared mechanically replacable module the constr uction of which is easily accessible. When the battery module is unplugged during operation, the module is also separated from the fan's air supply. Therefore the battery should only be replaced during oper ation, if production cannot be continued otherwise. If it is not possible to replace th e battery quickly, a second fan/battery module should be available for use during the replacement process. It should be plugged onto the NCU during replacement of the battery. In this context please note for the safety function of t he '840D sl' that it will switch off the module automatically after a certain time, if the fan is defect or not plugged in; this will protect the NCU from thermal destruction (see Manual: chapter Dual fan/battery module). Program Continuation: Clear alarm with the Delete key or NC START.
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 2101 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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