Sinumerik Alarm 25040 Axis %1 standstill monitoring

Sinumerik Alarm 25040 Axis %1 standstill monitoring

%1 = Axis name, spindle number

The NC monitors to ensure that the position is held at zero speed. Monitoring is started after a time that can be set for a specific axis in the machine data 36040 STSTILL_DELAY_TIME after interpolation has ended. A constant check is made to deter- mine whether the axis remains within the tolerance range given in MD 36030 STSTILL_POS_TOL.
The following cases are possible:
1. The interface signal SERVO ENABLE (DB31 – 48, DBX 2.1) is zero because the axis has jammed mechanically. Due to mechanical influences (e.g. high machining pressure), the axis is pushed away from the permissible position tolerance.
2. With closed position control loop (without jamming) – interface signal SERVO ENABLE (DB 31 – 48, DBX 2.1) is 1 – the axis is pushed away from its position by mechanical forces with a small gain in the position control loop.
The alarm can be reprogrammed in the MD ALARM_REACTION_CHAN_NOREADY (channel not ready).

– The NC switches to follow-up mode.
– Mode group not ready.
– Channel not ready.
– NC Start disable in this channel.
– Interface signals are set.
– Alarm display.
– NC Stop on alarm.
– Channel not ready.
– If the axis is a single axis when this alarm is triggered, the alarm is only effective for this axis (not effective for e.g. the channel or mode group)

Please inform the authorized personnel/service department.
• Check MD 36040 STSTILL_DELAY_TIME and MD 36030 STSTILL_POS_TOL; increase if necessary. The value must be greater than the machine data “Exact stop – coarse” ($MA_STOP_LIMIT_COARSE).
• Estimate machining forces and reduce if necessary by setting a lower feed or a higher rotational speed.
• Increase clamping pressure.
• Increase the gain in the position control loop by improved optimization (Kv factor MD 32200 POSCTRL_GAIN, 611D drive).

Program Continuation:
Clear alarm with the RESET key in all channels of this mode group. Restart part program.


  1. Siemens Diagnostics Guide by Siemens
Sinumerik Alarm 25040 Axis %1 standstill monitoring