Honeywell C300 User Manual

8. C300 Redundancy operation
8.5. Redundancy parameters
R500
April 2017
Series 8 C300 Controller User's Guide
Honeywell
213
Enable Synchronization - ENBLSYNCCMD
This command triggers an unsynchronized redundant module pair to attempt initial-
synchronization. Additionally, the module's Auto-Synchronization State transitions to
ENABLED (if previously set to DISABLED).
Disable Synchronization - DSBLSYNCCMD
This command triggers a synchronizing/synchronized/standby redundant module pair to
abort synchronization. Also, the module's Auto-Synchronization State to DISABLED.
Enable Standby - ENBLSTBYCMD
This command triggers a redundant controller pair in the Synchronization Maintenance
State to enter the Standby State. While in the Standby State, the secondary controller
contains a database that was previously synchronized with the primary controller but the
secondary is no longer receiving synchronization-data updates from the primary
controller. Specifically, after entering the Standby State, issue the switchover command,
and the controller with the stale database switches into the primary role with the CEE
execution state set to Idle. In the case where the Standby State was achieved through the
Enable Standby command, the Disable Synchronization command exits the Standby
State.
Auto-Synchronization State - RDNAUTOSYNC
Read-only parameter that reflects the current state of Auto-Synchronization as follows:
 Enabled upon receipt of the Enable Synchronization command. When enabled, a
Primary Module automatically attempts to synchronize the Secondary, upon receipt
of any Auto-Synchronization trigger (in addition to the Enable Synchronization
command).
 Disabled either upon receipt of the Disable Synchronization command or detection of
a persistent synchronization fault condition (such as, end-to-end checksum failure,
synchronization hardware failure, and so on). When disabled, user must explicitly
issue the Enable Synchronization command to reset any persistent fault condition and
(re)attempt initial-sync.
Auto synchronization triggers
When the primary controller has its Auto Synchronization State parameter set to enabled,
the redundant controller pair automatically commences initial-sync without user
intervention. More specifically, any action that results in the primary detecting a direct
compatible partner module triggers an initial sync attempt. Such as:
 Reconnection of the redundancy cable.

Honeywell C300 Specifications

General

Brand	Honeywell
Model	C300
Category	Controller
Language	English