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SINUMERIK 840C (IA)
3.5.3 USTACK, detailed error coding
The operating system can detect malfunctioning of the central processor, errors in
the system program or effects of incorrect programming by the user.
If the interpreter comes across an error during command processing or if another
error occurs that cause a program interruption, the PLC enters the STOP loop.
A more precise analysis of the error can be obtained using the programmer or the
detailed error coding integrated into the control. The interrupt stack and the de-
tailed error coding are available for this, which are kept up-to-date in the Installa-
tion List up to SW4 and in the Diagnostics Guide for SW5 and higher.
Selection SUp to software version 2:
SK Diagnosis” –> SK NC diagnosis” –> SK Service display” –> SK PLC
error detection
SOn software version 3 and higher:
SK Diagnosis” –> SK Service display” –> SK PLC service
Fig. 3.2 Detailed error code for cause of PLC stop
3 PLC Installation
3.5.3 USTACK, detailed error coding
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