8. C300 Redundancy operation
8.5. Redundancy parameters
216
Series 8 C300 Controller User's Guide
Honeywell
R500
April 2017
Last Synchronization Time - SYNCTIMEBEG
The SYNCTIMEBEG parameter indicates the wall-clock time at which the redundant
controller pair last transitioned into the Synchronization Maintenance State. This time
updates on every transition into the Synchronization Maintenance State.
Last Lost of Sync Time - SYNCTIMEEND
The SYNCTIMEEND parameter indicates the wall-clock time at which the redundant
controller pair last transitioned out of the Synchronization Maintenance State. This is
updated on every transition out of the Synchronization Maintenance State.
Redundancy Traffic
The RDNXFERAVG and RDNXFERMAX parameters indicate the average and
maximum redundancy traffic in bytes per second. These values are reset upon issuing
the C300 Platform block's Stats Reset command.
Redundancy Delay
The RDNDELAYAVG and RDNDELAYMAX parameters indicate the average and
maximum redundancy delay as a percentage of control execution. This serves as a
measure of the secondary-to-primary back-pressure that varies with the secondary
controller's load of redundancy data to be processed. These are reset upon issuing the
C300 Platform block's Stats Reset command.
Conditions that result in loss of sync
Assuming a synchronized or standby redundant controller pair, the following conditions
result in loss of synchronization.
Disable Sync command (from Primary or Secondary Platform FB).
Redundancy cable (private path) between Primary and Secondary controllers is lost.
Both IOL channels connected to Secondary C300 I/O Link X are lost where:
X is the I/O Link number (that is, equally applies to either I/O Link).
The IOLINK Type for this I/O Link has a value other than NONE.
Both IOL channels connected to Primary C300 I/O Link X are lost where:
X is the I/O Link number (that is, equally applies to either I/O Link).
The IOLINK Type for this I/O Link has a value other than NONE
