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