Siemens alarm 25040: Axis %1 standstill monitoring

What it means

After interpolation ended and the standstill delay (MD36040 $MA_STANDSTILL_DELAY_TIME) expired, the axis drifted outside the standstill window (MD36030 $MA_STANDSTILL_POS_TOL). The NCK detects that a commanded-stationary axis is being pushed out of position, either with servo enable removed or with a soft position loop under external force.

Likely causes

• Mechanical jam or heavy cutting force pushing the axis
• Vertical axis dropping on failing brake or counterbalance
• Position loop gain (Kv, MD32200) too low
• Tolerances set tighter than exact-stop settings