Bryan Boilers Triple-Flex 150 ユーザーズマニュアル

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Date:  
8-4-2010 
 
Revision: 0 
 
Form:  
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off all slaves and enters an idle or standby 
condition. 
 
4.7.2 P
ERIODIC 
D
ATA 
P
OLLING 
MESSAGES
 
 
The LL master uses polling to discover new 
slave Sola devices and to periodically refresh 
the information it has about a known slave Sola 
devices. Thereafter it polls the known devices to 
make sure they are still present and to obtain 
updated status information. It also periodically 
polls the entire slave address range to discover 
any new slave devices. A polled Sola is read to 
determine the values of the following data items: 
a. The slave's type (compatibility) as indicated 
by the Slave type b. The slave enable status 
Slave enable 
c. The slave mode as set in Slave 
mode 
d. The slave sequence order as set in 
Slave sequence order 
e.  Demand-to-firing 
delay: mm:ss or None 
This delay time is 
needed by the LL master to determine the length 
of time to wait between requesting a slave Sola 
to fire and detecting that it has failed to start. It 
should be set to the total time normally needed 
for the burner to transition from Standby to Run, 
including such things as transition to purge rate, 
prepurge time, transition to lightoff rate, all 
ignition timings, and some extra margin. f. CT - 
Burner run time 
This parameter will be needed 
if measured run-time equalization is being used. 
 
Slave Control 
The LL master sends each active slave a 
command and also performs a slave status read 
for each known slave device. It also sends a 
Master status broadcast that is heard by all 
slaves. There are 5 commands that might be 
sent: 
• All slaves are commanded to turn off and 
remain off. 
• The LL master sends message to Solas that 
are off, to turn their fans on. 
• The LL master suspends operation which 
request a burner to recycle and remain in 
Standby if it has not yet opened its main valve 
(e.g. it is in Prepurge or PFEP) but to keep firing 
if it has reached MFEP or Run. This suspend 
may be for the fan to be on or off in standby. 
This message is used to abort the startup of a 
slave that is not yet firing (because demand 
went away just before it was firing), but to keep it 
on if it actually is firing (the LL master will 
discover what happened in a subsequent status 
response). The LL master also sends this 
message to a slave that is OnLeave. (This 
ensures that if the slave is firing when it returns 
to LL master control, it will stay that way until the 
master has decided whether to use it; or 
conversely, if the slave stops firing for some 
reason that it will not start up again until the LL 
master has requested this. In either case, the 
command will be to turn on the off cycle fan if 
any other slave burners are firing, or to turn the 
fan off if the slave is the only slave that might (or 
might not) be firing. 
• The LL master sends message to turn the 
burner on and to assign the burner’s firing rate. 
If the commanded modulation rate is less than 
the burner’s minimum modulation rate, then the 
burner should always operate at its minimum 
rate. 
 
4.7.3 S
LAVE 
S
TATUS 
M
ANAGER
 
 
The LL master keeps track of slave status for 
each Sola that is enabled as a slave device. The 
slave status manager operates internally for 
each slave Sola devices (up to 8). There is a 
table entry for each device containing the 
following data: 
• SlaveState: 
Unknown - indicates the table entry is unused 
and empty 
Available - indicates the slave is OK and ready 
to use, but is not 
currently firing as a slave 
AddStage - stage is getting ready to fire 
SuspendStage - stage was getting ready but is 
not needed 
Firing - indicates the slave is currently firing 
OnLeave - indicates the slave is operating for 
some other demand source within it that has 
higher priority than slave demand. 
Disabled - indicates the slave is locked out or 
disabled in some way 
Recovering - indicates the slave is in a time 
delay to ensure that it is OK before it is again 
considered to be available. 
•  RecoveryTime: Saves how long the slave 
must be OK to recover. 
•  RecoveryTimer: Used to measure the slaves 
recovery time 
•  RecoveryLimitTimer: Enforces a maximum 
slave recovery time 
•  DataPollFaultCounter: Used to tolerate 
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