Siemens SINUMERIK codes
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Siemens SINUMERIK Controller

Program/G-code · Intermediate · 30-60 minutes

Alarm 20149

Siemens 20149 - Block motion-synchronous action: Index is illegal

An illegal index was used to access a variable in the motion-synchronous action. The illegal index is displayed. Example. DO $R[$AC_MARKER[1]] = 100 The error occurs if the value of marker 1 is greater than the maximum permissible R-parameter number. PROFIBUS/PROFINET I/O: An illegal slot / I/O area index was used while reading/writing data. Cause: 1.: Slot / I/O area index >= max. number of available slots / I/O areas. 2.: Slot / I/O area index references a slot / I/O area that has not been configured. 3.: Slot / I/O area index references a slot / I/O area that has not been released for system variables Control reaction: NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Siemens SINUMERIKProgram/G-codeIntermediate30-60 minutes

20149

Siemens 20149 - Block motion-synchronous action: Index is illegal

Block motion-synchronous action: Index is illegal

An illegal index was used to access a variable in the motion-synchronous action. The illegal index is displayed. Example. DO $R[$AC_MARKER[1]] = 100 The error occurs if the value of marker 1 is greater than the maximum permissible R-parameter number. PROFIBUS/PROFINET I/O: An illegal slot / I/O area index was used while reading/writing data. Cause: 1.: Slot / I/O area index >= max. number of available slots / I/O areas. 2.: Slot / I/O area index references a slot / I/O area that has not been configured. 3.: Slot / I/O area index references a slot / I/O area that has not been released for system variables Control reaction: NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Safety

  • Only qualified personnel should diagnose and clear control alarms; follow the machine builder's safety procedures and lockout/tagout where hardware work is required.

Common Causes

  • An illegal index was used to access a variable in the motion-synchronous action.
  • The illegal index is displayed.
  • Example: ... DO $R[$AC_MARKER[1]] = 100 The error occurs if the value of marker 1 is greater than the maximum permissible R-parameter number.

Troubleshooting Steps

  1. 1Use a valid index.
  2. 2Clear alarm with the RESET key. Restart part program

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