At a Glance

This field gives access to various simulation buttons:

  • Warm restart,

  • Cold start,

  • Output fallback.

Operating Mode field:

This field also indicates the date, time and cause of the last PLC stop.

Description

Buttons and functions:

Button

Function

Warm restart

Click on this button to perform a warm restart of the PLC.

This sets the %S1 bit to 1, which, for example, is used to command a partial initialization program.

This does not set %S21 and %S13.

Cold start

Click on this button to perform a cold start of the PLC.

This initializes the data, the system, and sets the %S0 bit to 1 which (in this case) is used for example to command a specific initialization program.

This does not sets %S21 and %S13.

Output fallback

It is used to switch the outputs into fallback mode. The values supplied to the outputs are then the values defined in the configuration (fallback value on PLC STOP).

When the outputs are in fallback, the Applied outputs button becomes active and allows you to exit fallback mode.

Applied outputs

Is used to stop the fallback mode and to reapply the values supplied by the program to the outputs.

Specific features

Management of output fallbacks for Premium Atrium, M580 and M340 PLCs: when a task is set to STOP, the associated outputs automatically switch to the configured mode (fallback or maintain). The outputs associated with the other tasks continue to be updated as normal.

For Premium PLCs, during a warm start, an output in fallback or maintain mode goes to the security mode (state 0) while the CPU is not started. When the CPU is started, if the output falback function is still active, the output will return to the fallback mode or stay at 0 in maintain mode.

For M580, refer to chapter BMEP58xxxx CPU Operating Modes.

For M340 PLCs

  • Whatever the operating mode, an output in fallback or maintain mode do not return to the previous state but stays in security mode (state 0) while the fallback condition is applied.

  • The fallback values are only applied if the Topological option of Memory Management is checked, see in the PLC configuration screen.

NOTE: The buttons Output fallback and Applied Outputs are not available for Quantum PLCs. On Quantum PLCs, the output of the stopped task will continue to be updated (with the last value written), the others are handled normally. Inputs of the stopped task will continue to be scanned, but the data input will be discarded.