CNC troubleshooting answers
18 questions with answers cited from the manufacturer manuals.
- 0SINUMERIK 840D sl alarm 25050 during contouring, what to check?
Alarm 25050, "Axis contour monitoring," on a SINUMERIK 840D sl indicates that an axis's actual position deviates from the expected position by more than the defined contour tolerance (MD36400). This typically occurs duri…
- 0SINUMERIK 840D sl alarm 25040: axis moves at standstill, what to check?
Alarm 25040 on a SINUMERIK 840D sl indicates that an axis, which should be stationary, has moved beyond its allowed position tolerance. This monitoring activates after a delay once interpolation has finished. Common caus…
- 0SINUMERIK 840D sl Alarm 25000, active encoder hardware fault: what to check?
Alarm 25000 on a SINUMERIK 840D sl signifies a hardware fault with the active encoder, meaning its signals are missing, out of phase, or have a ground/short circuit. This causes the NC to switch the axis to follow-up mod…
- 0Haas NGC Alarm 160: Low Incoming AC Line Voltage at power-up, what to check?
Alarm 160 on a Haas Next Generation Control (NGC) indicates that the incoming AC line voltage to the machine is less than 80% of the expected value. This condition prevents the machine from operating until corrected. The…
- 0Haas NGC Z-axis Alarm 3.103 after tool change, why?
Alarm 3.103 on a Haas NGC indicates the Z-axis cannot reach its commanded position because the following error became too large. This often occurs during cutting, rapid moves, or on the first move after servo-on, especia…
- 0Haas NGC Alarm 102 SERVOS TURNED OFF after E-stop, what to check?
Alarm 102 SERVOS TURNED OFF on a Haas Next Generation Control (NGC) indicates that the servo motors are currently off. This is a state, not a root cause, and typically occurs after power-on, an emergency stop, or another…
- 0Haas NGC 3.108 AXIS SERVO OVERLOAD on Z-axis during heavy cut, what to check?
Alarm 108 AXIS SERVO OVERLOAD on a Haas NGC means an axis motor sustained a load over 100% for an extended period. The prefix '3.' indicates the Z-axis. This alarm is distinct from a servo error (103) where the axis cann…
- 0FANUC 0i-F DS0307 APC ALARM: BATTERY LOW 1, what to check first?
The DS0307 alarm on a FANUC 0i-F controller indicates that the absolute position detector battery voltage is low and requires replacement. The position data is still held, but the battery should be replaced soon to preve…
- 0FANUC 0i-F DS0306 APC ALARM: BATTERY VOLTAGE 0 after weekend shutdown, what to check?
The DS0306 alarm on a FANUC 0i-F controller indicates that the absolute position detector battery voltage has dropped to a level where position data can no longer be held, or a Pulsecoder was powered for the first time. …
- 0FANUC 0i-F DS0300 after power-up, what to check first?
The DS0300 alarm on a FANUC 0i-F indicates that the absolute position detector needs its zero position reset because the link between the reference position and the encoder's counter has been lost. This typically happens…
- 0FANUC 0i-F PS0090: Reference return incomplete after power-up, what to check?
The PS0090 fault on a FANUC 0i-F indicates that the reference position return could not be completed normally. This can occur if the return started too close to the reference position, the return speed was too slow, or i…
- 0FANUC 0i-F OT0500 after power-up, limits seem to have moved: what to check?
The OT0500 alarm on a FANUC 0i-F indicates that an axis has exceeded its positive-side software travel limit, which is set by parameter 1320. This limit is in machine coordinates, so its accuracy depends on the axis's re…
- 0FANUC 0i-F SP9012 OVERCURRENT POWER CIRCUIT on spindle start, what to check?
The SP9012 (OVERCURRENT POWER CIRCUIT) alarm on a FANUC 0i-F CNC indicates an abnormally high spindle motor current. This fault often occurs at spindle start or acceleration, especially after a motor or amplifier change,…
- 0FANUC 0i-F SP9001: Spindle motor overheat, what to check first?
The SP9001 (MOTOR OVERHEAT) alarm on a FANUC 0i-F indicates the spindle motor's internal temperature has exceeded its specified limit. This often happens when the motor is used beyond its continuous rating or its cooling…
- 0FANUC 0i-F SV0436 on Z-axis after heavy cuts, what to check?
The SV0436 (SOFTTHERMAL(OVC)) alarm on a FANUC 0i-F indicates that the digital servo software has detected a software thermal overload condition. This means the motor current remained high for an extended period, trigger…
- 0FANUC 0i-F SV0411 on Z-axis during rapid traverse, what to check?
The SV0411 (EXCESS ERROR (MOVING)) alarm on a FANUC 0i-F controller indicates that the positional deviation of an axis while moving exceeded the limit set in parameter 1828. This means the motor couldn't keep up with the…
- 0FANUC 0i-F SV0410 on vertical axis after E-stop, what to check?
The FANUC 0i-F SV0410 alarm indicates that the positional deviation of an axis while it was commanded to be stopped exceeded the limit set in parameter 1829. This typically occurs when an external force or gravity causes…
- 0FANUC 0i-F SV0401 IMPROPER V_READY OFF on multiple axes, what to check?
The FANUC 0i-F SV0401 IMPROPER V_READY OFF alarm indicates that the velocity-control ready signal (VRDY) from the servo amplifier was OFF while the position-control ready signal (PRDY) was ON. This means the amplifier st…