System diagnostic

At a Glance

The system diagnostic is performed automatically. When the PLC detects a system error (for example, a watchdog being exceeded, an input/output error, division by zero, etc.), information is sent to the diagnostic viewer. The diagnostic viewer will display a system error message if you have checked the System diagnostics checkbox.

NOTE: As with the project diagnostic, the information viewed on the Viewer comes from the PLC's diag buffer, consequently the events are dated at the source and give the precise status of the process monitored.

Implementation

The following table describes the procedure to follow to use the system diagnostic on the Premium, Atrium and Quantum PLCs in Control Expert.

Step	Action
1	Select Tools → Project Settings Result: the project settings configuration window is displayed.
2	In the Diagnostics area on the Build tab, check the System diagnostics checkbox.
3	Confirm with OK.
4	Build your project.
5	Transfer your project to the PLC.
6	Open the Diagnostic Viewer by selecting: Tools → Diagnostic Viewer. Result: the system diagnostic is operational and each system alarm now appears in the Viewer.

List of system alarms monitored

The following table summarizes the system information monitored automatically by the system diagnostic service.

System object	Succinct description of the alarm
%S10	Input/output error
%S11	Watchdog overflow!
%S15	Character string fault
%S18	Overflow or arithmetic error
%S19	Task period overrun
%S20	Index overflow
%S39	Saturation in event processing
%S51	Time loss in real time clock
%S65	Extract card command
%S66	Backup application to the memory card
%S67	State of the PCMCIA application memory card battery
%S68	State of processor battery
%S76	Diagnostic buffer configured
%S77	Diagnostic buffer full
%S96	Previously backup program
%S118	General Fipio I/O fault
%S119	General in-rack I/O fault
%SW0	Master task scanning period
%SW1	Fast task scanning period
%SW2	Period of auxiliary task scanning 0.
%SW3	Period of auxiliary task scanning 1.
%SW4	Period of auxiliary task scanning 2.
%SW4	Period of auxiliary task scanning 3.
%SW11	Watchdog duration
%SW17	Error status for floating operation
%SW76	Diagnostic function: save
%SW77	Diagnostic function: de-registration
%SW78	Diagnostic function: number of errors
%SW96	Save/restore %MW in flash memory.
%SW97	Storage card error code
%SW125	Type of blocking error
%SW146	Fipio bus arbiter function display
%SW153	List of Fipio channel manager faults
%SW154	List of Fipio channel manager faults