Installation manual

REDUNDANT SYSTEMS
53
6
On the Standby controller, the comparison of the local/remote data is based on a table that
summarizes the configuration of the validating rules that contains the following parameters
both for the encoders and for the presence sensors:
Validation procedure enabling/disabling flag.
Pending alarm validation filter (number of consecutive times the alarm is notified from the
Standby to the Active controller).
For more information about Diagnostics messages see the Parameters HELP in Genius.
Validation of the Parcel Error Count Condition
The validation of the role of the active controller is also performed by the Standby controller,
based on a parcel error count condition (comparison between Standby and Active
controllers). A failure in the validation procedure leads to the switch over.
A parcel error count condition is determined by the following parameters:
Max Consecutive Lost Parcels: The Standby controller recognizes n more consecutive
Parcels than the Active controller. Error number [163]
Max % Of Lost Parcels (Out Of 100 Parcels): The Standby controller recognizes n out of
100 Parcels counted that the Active controller has not counted. Error number [165]
These error conditions do not generate diagnostic alarms since they cannot immediately
determine whether the fault is related to the presence sensor or the encoder. The two
conditions are however registered with their specific error numbers in the debug log as cause
for the switch over.
For either condition, WebSentinel signals simultaneous presence sensor and encoder faults.
After the switch over is concluded, the Standby (ex-Active) controller will establish whether
the fault is due to the presence sensor or the encoder. This may not be possible for particular
cases: i.e. Encoder Timeout, PS Timeout parameter combinations; slow conveyor speeds,
percentage error count condition.
6.5.2 WebSentinel Interface
WebSentinel ignores the redundant architecture and connects only to the controller that is
currently active. This is the only practical scenario with the current implementation of
WebSentinel and means that the only possible policy for the IP address association in the
event of a switch over is to the controller redundancy role (“seen” IP address remains
unchanged after switch over).
WebSentinel Standard/Redundancy and Related Diagnostics
The companion controllers must be configured so that their IP address is associated to their
redundancy role, this way WebSentinel always “sees” the same IP address regardless of
which controller is active.
WebSentinel interfaces only to the active controller and has no knowledge about the Standby
controller and its IP address.
In the event of a switch over, WebSentinel will connect to the new active controller.