CleaverBrooks CFC-500 Operation, Service And Parts Manual page 212

CB FALCON
Sequencer Drop Lag Boiler Selection
When the stager asks the sequencer for a lag boiler to drop the
sequencer looks at the StagingOrder numbers of all Firing
boilers. If only one Firing boiler is found, or none are found,
then this selection function returns a value that indicates no
boiler may be dropped. Otherwise it returns an identifier for the
boiler having the highest StagingOrder number.
Alert and Fault message information is shown in APPENDIX C.
750-265
Sequencer 1 Minute Event
Part of the sequencer is called by the timing service at a 1
minute rate to implement lead rotation.
The 1 minute event checks the boiler identified by
LeadBoilerSeqNum. If it is Firing then the LeadBoilerRunTime
is incremented.
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