Código 25020: Axis %1 zero mark monitoring of active encoder
Descripción del problema y advertencia de seguridad
El Siemens SINUMERIK 840D CNC ha desencadenado una alarma crítica Axis %1 zero mark monitoring of active encoder. Se requiere la atención inmediata de un operador calificado o técnico de mantenimiento para evitar daños secundarios al equipo o piezas estropeadas durante el ciclo de fabricación. Asegúrese siempre de seguir los procedimientos de seguridad estándar y LOTO antes de acceder a los armarios eléctricos.
Pasos oficiales de solución de problemas
Parameters: %1 = Axis name, spindle number Definitions: For PROFIdrive: The position encoder pulses between 2 zero mark pu lses are counted, and the plausibility is assessed (The functionality and possibly the par ameteritation of the plausibility check is done on the drive side. Please refer to the relevant drive documentation fo r details.), and reported in a PROFIdrive message frame (encoder interface) to the control, which then issues the present alarm. The alarm can be reprogrammed in MD11412 $MN_ALARM_REACTION_CHAN_NOREADY (channel not ready). Reaction: Mode group not ready. The NC switches to follow-up mode. Channel not ready. NC Start disable in this channel. Axes of this channel must be re-referenced. Interface signals are set. Alarm display. NC Stop on alarm. Channel not ready. Remedy: Please inform the authorized personnel/service department. The differences can result from transmission erro rs, disturbances, encoder har dware faults or from the evaluation electronics in the encoder used for position control. Th e actual value branch must therefore be checked: 1. Transmission path: Check the ac tual-value connectors for corr ect contacting, encoder cable for continuity, and also check for shor t-circuits and groundi ng (loose contact?). 2. Encoder pulses: Is the encoder power supply within the tolerance limits? 3. Evaluation electronics: Replace or rec onfigure the drive or encoder module used. Monitoring can be switched off by setting MD36310 $MA_ENC_ZERO_MONITORING [n] to 0 or 100 (n = encoder number: 1, 2). Program Continuation: Clear alarm with the RESET key in all channel s of this mode group. 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.
Acerca de las alarmas de Siemens SINUMERIK 840D CNC
Los controladores industriales construidos por Siemens están diseñados con amplios sistemas de diagnóstico para proteger los circuitos internos y los enlaces mecánicos. Cuando un SINUMERIK 840D CNC arroja un código de error como 25020, generalmente indica un desajuste entre los valores ordenados y la retroalimentación real del sensor.
Lista completa de alarmas: 4014 Siemens SINUMERIK 840D CNC códigos.
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