Bryan Boilers & 300 ユーザーズマニュアル

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Date:  
8-4-2010 
 
Revision: 0 
 
Form:  
2396
 
momentary communication problems and to act 
on these if they are excessive. • 
StatusReadFaultCounter
: Used to tolerate 
momentary communication problems and to act 
on these if they are excessive. 
•  AbnormalFaultCounter: Used to tolerate 
momentary abnormality 
•  StagingOrder: Used to record the stage-on 
order, for use by the sequencer when it needs to 
drop a stage. 
• Storage for each item described in the Periodic 
data polling section • Storage for each item 
described in the Slave status read response 
section • Slave Command - the command word 
from the master to the slave. 
Features common to all states 
• Whenever a slave Sola device is not in an 
expected condition then a recovery function is 
used to set up timers to give a faulty slave: — 
minimum time that it must appear to be OK, and 
— limit how long a slave has to recover from any 
error. 
• If the slave status read was bad then the 
slave's FaultCounter is incremented and if it to 
reaches the fault value tries, then a recovery 
action is invoked. This action does nothing else 
if the status read was Bad. If the slave status 
read was OK then the status function puts the 
slave read response data in a slave status table. 
If a transition to another state is indicated then 
the  SlaveState  is simply set to the indicated 
state. 
 
Data poll response handling  
 
Valid Response Message  
 
When a slave Sola responds with a properly 
formatted  message it is examined to see if 
Slave enable 
value is "Enable for Sola Master". 
• If the "Enable for Sola Master" value is not 
present then  the slave status table is checked 
and if the slave is not  in the table then the 
message is ignored (this is normal). However if 
the slave is in the table then the message is 
stored as usual and the slave will invoke the 
action as a  disabled slave and cause recovery 
action to occur. 
• If the "Enable for Sola Master" value is present 
then the slave status table is checked and if the 
slave is not in  the table then the slave data is 
stored in an empty  position in the table. 
However if the slave is in the table  then the 
message is stored as usual (this is the normal 
case).  
 
INVALID RESPONSE OR NO RESPONSE 
 
When a Sola responds to a data poll with an 
improperly formatted  message or it does not 
respond then the slave  status table is checked 
and: If the polled slave device is in the table then 
the  Data Poll Fault is noted. If this causes a 
fault counter to exceed the fault value then the 
SetRecovering handling is invoked. 
 
SlaveState states 
Recovering 
A slave that is recovering is 
checked once per second.  If the slave has 
recovered the SlaveState  table is changed to 
Available.  If the slave has not yet recovered 
when its recovery timer reaches the 
RecoveryTimeLimit 
then: If the slave is not 
enabled for the Sola LL master its SlaveState 
table is Set to Unknown (which logically 
removes it from the slave table). Otherwise the 
Recovery- LimitTimer 
is cleared which starts a 
new recovery measurement and the slave 
remains in recovery (indefinitely).  
 
Available 
A slave in the Available state remains 
that way until the Stager moves it into the 
AddStage state or the ProcessSlaveStatus 
action moves it to some other state. 
AddStage 
A slave in the AddStage state 
remains that way until the ProcessSlaveStatus 
moves it to Firing or some other state, or the 
Stager times out and moves it into the 
Recovering state if it fails to fire. 
SuspendStage 
A slave in the SuspendStage 
state remains that way until the 
ProcessSlaveStatus moves it to some other 
state, or the Stager times out and moves it into 
either the Firing or the Available state. 
Firing 
A slave in the Firing state remains that 
way until the ProcessSlaveStatus moves it to 
some other state, or the Stager drops the stage 
and moves it into the Available state. 
OnLeave 
A slave in the OnLeave state remains 
that way until the ProcessSlaveStatus moves it 
to some other state. 
Disabled 
A slave in the Disabled state remains 
that way until the ProcessSlaveStatus moves it 
to Recovering. 
 
Demand and Priority 
 
Different sources of demand can cause the LL 
master to operate in different ways. These 
sources have a priority relationship. 
 
CH Demand 
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