Filter
Top Products
Using a Quantum IEC Hot Standby System
840 USE 106 00 January 2003 125
Updating Project
Section Data
All DATA of a section will be fully updated every scan if it is equal to its counterpart
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,
Counters, 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:
With 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
logic.
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
changes.
The change of a literal during animation (called quickwrite) will cause the whole
section not to be updated or transferred to the Standby Controller.