Schneider Electric 840 USE 106 0 manual Logic

Using a Quantum IEC Hot Standby System

Updating Project All DATA of a section will be fully updated every scan if it is equal to its counterpart

Section Data on the Primary controller. Section DATA will not be updated at all if it is not equal to its counterpart on the Primary controller.

The section data that is updated if the sections are equal on Primary and Standby controllers is:

Internal states of Elementary Function Blocks (EFBs) used in the section (Timers,

lCounters, PID, etc.)

All Derived Function Block (DFB)-Instance data blocks of each DFB instantiated in the section including nested DFBs

Hot Standby behavior for the section update process is:

lWith matching logic, all section data gets updated on the Standby controller After you do an online change to a section, none of its local data gets updated. To get it updated again, the controllers’ logic has to be equalized via the CHS transfer button or a complete download to the Primary controller with differing

llogic.

It is not possible to make online changes to one controller and the same online changes to the other controller to get matching logic again. To equalize both controllers, you should either push the Transfer button of the CHS module or do a completer download to the controller which did not receive the download

lchanges.

The change of a literal during animation (called quickwrite) will cause the whole section not to be updated or transferred to the Standby Controller.

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