What causes Siemens SINUMERIK alarm 1018?

Parameter or machine data configuration error. Hardware fault on the NC or drive component. Part program error or illegal command. Communication fault between NC and drive or I/O modules. Software or firmware error requiring system restart.

How do I fix Siemens SINUMERIK alarm 1018?

1. Note the complete alarm text including any axis, channel, or block number values. 2. Check for related alarms active simultaneously in the SINUMERIK alarm list. 3. Power cycle the machine to clear transient faults. 4. Review the SINUMERIK machine data for parameters related to the alarm. 5. Consult the Siemens SINUMERIK alarm manual for alarm 1018 detailed remedy.

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Siemens SINUMERIK Controller

Program/G-code · Intermediate · 30-120 minutes

Alarm 1018

Siemens 840D 1018 - Floating point arithmetic error in channel task station FPU

Alarm 1018 indicates a floating-point arithmetic error in the CNC's calculation unit (FPU - Floating Point Unit). This typically occurs when the NC program or PLC performs an illegal mathematical operation such as division by zero, square root of negative numbers, logarithm of zero/negative values, or calculations resulting in values exceeding the numerical range limits of the control system.

Siemens SINUMERIKProgram/G-codeIntermediate30-120 minutes

1018

Siemens 840D 1018 - Floating point arithmetic error in channel task station FPU

Floating point arithmetic error in channel task station FPU

Root Cause Summary

Alarm 1018 indicates a floating-point arithmetic error in the CNC's calculation unit (FPU - Floating Point Unit). This typically occurs when the NC program or PLC performs an illegal mathematical operation such as division by zero, square root of negative numbers, logarithm of zero/negative values, or calculations resulting in values exceeding the numerical range limits of the control system.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Note the exact channel, task, and station numbers from the alarm display and identify which NC program was active when the alarm occurred.
2
Review the NC program block where execution stopped, focusing on mathematical functions (DIV, SQRT, LN, LOG, TAN, ATAN, SIN, COS) and R-parameter calculations. Check for division operations where the divisor could become zero.
3
Examine R-parameters, system variables, and GUD (Global User Data) values used in calculations. Use the variable monitor to check their actual values at the point of error.
4
Correct the program logic by adding range checking, conditional statements, or default values to prevent illegal mathematical operations. Test in single block mode after correction.

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