Rockwell Automation 1756-RMxx ControlLogix Enhanced Redundancy System User Manual - Manual (Page 238)

238 Rockwell Automation Publication 1756-UM535D-EN-P - November 2012
Appendix B Event Log Descriptions
Modules chassis state rule A check to choose a primary chassis if both chassis power up at the same time. Suppose that the modules in one chassis
are already in a primary state. In that case, that chassis becomes primary.
NRC modules rule A check to choose a primary chassis if both chassis power up at the same time. NRC stands for nonredundancy compliant.
Suppose that a module in one of the chassis doesn't support redundancy and all the modules in the other chassis do
support redundancy. In that case, the other chassis becomes primary.
Partner not on same link A primary communication module cannot communicate with its partner across the network. For example, a 1756-CN2R/
B communication module in the primary chassis cannot communication with its partner 1756-CN2R/B communication
module in the secondary chassis.
These conditions may result in this event:
• A network anomaly, such as noise, a poor connection, or a termination anomaly, exists.
• The secondary communication module is not connected to the same network as the primary or any network at all.
Powerdown time rule A check to choose a primary chassis if both chassis power up at the same time. If the two chassis powered down more
than one second apart, the last chassis to power down gets the first chance at being primary.
Primary became PTP time synchronized The primary module is now PTP synchronized and an auto qualification was requested.
Program Fault A controller has a major fault.
PTP not synchronized A redundant controller's PTP clock is not synchronized or the partner controller pair is synchronized to different
grandmasters.
PTP now synchronized PTP is now synchronized on the module.
1756-RM OS error The redundancy module has an anomaly.
1756-RM serial number rule A check to choose a primary chassis if both chassis power up at the same time. This is the final tie-breaker. The 1756-RM
with the lower serial number gets the first chance to become primary. It becomes primary as long as the other chassis
isn't more able to control the system.
Standby secondaries rule A check to choose a primary chassis if both chassis power up at the same time. Because standby isn't available yet, this
check always ends in a tie.
SYS_FAIL_L Active A module has a nonrecoverable fault or lost its connection to the network. When that happens, the SYS_FAIL signal
becomes true.
The backplane of the chassis has a SYS_FAIL signal. Each module in the chassis uses this signal to indicate an anomaly:
• The signal is normally false (inactive), which means that all modules in the chassis are OK.
• A module turns the SYS_FAIL signal true (active) when the module has a nonrecoverable fault or it losses its
connection to the network.
Look for later events to find out what happened:
• If you see a Module Removal event shortly afterward, then a module has a nonrecoverable fault. Double-click the
Module Removal event to see the slot number of the module. The SYS_FAIL signal may stay true until you cycle
power or remove the faulted module.
• If you see a SYS_FAIL_L Inactive event within a few hundred milliseconds, then a cable is probably disconnected or
broken. A communication module pulses the SYS_FAIL signal when the module loses its connection to the network.
Look for a Transition to Lonely event to see which module lost its connection.
The partner RM has been connected The partner 1756-RM powered up or become connected by the fiber-optic cable.
The partner RM screamed The partner 1756-RM lost power, has an unrecoverable fault, or was removed.
An 1756-RM has circuits that hold power long enough for it to send a message to its partner over the fiber-optic
interconnect cable. The 1756-RM sends the message even after you remove it from the chassis. This message is called a
scream. The scream lets the partner 1756-RM tell the difference between a broken fiber-optic interconnect cable and the
power loss or removal of the primary 1756-RM.
• If the fiber optic cable breaks, then there isn't a switchover.
• If the redundancy module loses power or is removed, then there is a switchover.
Transition to lonely A communication module doesn't see any other devices on its network. This usually means that the network cable of the
module is disconnected or broken. The event log shows Transition to Not Lonely when you reconnect the cable.
Unicast not supported A unicast connection is configured in the redundant controller, and enhanced redundancy systems do not support
Unicast.
Unknown event The 1756-RM configuration tool may be an older version and must be updated.
WCT time change (> 1 second) The clock of the 1756-RM changed. This happens when you:
• use the RMCT to set the clock.
• connect the redundancy module to another redundancy module that is already the primary. The redundancy module
synchronizes its clock to that of the primary 1756-RM.
Event Description Description