WinCC diagnosis
6
6.1 Runtime Monitoring of Actions
Introduction  
WinCC script processing is a very open system. It allows Windows APIs and dedicated DLL 
functions to be called. The underlying programming language C is very comprehensive and 
offers a high degree of freedom. Incorrect implementation of these capabilities can also lead 
to crashing the system. Incorrect configuration can also seriously decrease the performance 
of the system.
The ApDiag.exe diagnostics tool should be used to support the analysis of errors and 
performance problems. Note that the diagnostics application itself will affect performance; 
collecting additional values costs time. Individual diagnostic functions can therefore be 
activated and deactivated to avoid degrading the runtime of the system during operation. 
This is why you should ensure that the diagnostic functions are deactivated during the final 
commissioning stage.
This description will not explain every possible item of diagnostic information in detail, since 
sound knowledge of the system architecture is required to understand it. The purpose of this 
description is to indicate possibilities and handling of the ApDiag diagnostics tool so that 
ApDiag can be utilized as intended should the need arise. 
WinCC: General information and installation
System Manual, 02/2017, A5E40840020-AA 163