Bryan Boilers 250 Manual De Usuario

 

Date:  

8-4-2010 

 

Revision: 0 

 

Form:  

2396

 

following sources of demand. All sources that 
are currently calling for heat will be true (multiple 
items may be true at the same time) except 
when WWSD is active, then CH demand is 
inhibited. 
 
CH Demand 
CH Frost demand – true if any slave is calling for 
CH frost protection and Frost protection 
enable 

is true. 

 

 
Is a data item which contains the identity of a 
single source of demand that the LL Master is 
currently serving according to its priority: 
• None – no active service, LL master is idle 
• CH 
• Frost – burner demand is true for frost 
protection 
• WWSD – no high priority demand is active, and 
WWSD is inhibiting CH demand (if any).  
 
MASTER SERVICE STATUS 
 
Is a data item used by pump control logic that 
combines the Master Heat Demand and Master 
Active Service data. It is implemented as 
described by the Pump Control Block diagram. 
 
Outdoor Temperature 
 
For a Sola that hosts a LL master, the outdoor 
temperature may be known from either of two 
sources. If the host Sola has an outdoor sensor 
that is reporting a valid temperature then this 
sensor reading is used. Otherwise, if any slave 
Sola is reporting a valid temperature as part of 
its Data Poll message, then this temperature is 
used. 
 
The resulting outdoor temperature provides all 
outdoor temperature needs for both stand-alone 
and LL master purposes. If neither source has a 
valid temperature then the outdoor temperature 
is simply invalid and unknown, and the functions 
which need this information handle it accordingly 
per their individual definitions. 
 
Modulation 
 
Each demand source has one or more setpoints 
that may be active and an operation sensor. 

These are used to detect turn-on and turn-off 
conditions. The difference between operating 
point and setpoint determines the LL master's 
firing rate 
 

 
LL MODULATION SENSOR: S5 
The LL master's modulation sensor uses the S5 
sensor (connector J8 terminal 11 and 12). If the 
LL master is enabled and its sensor is faulty 
then an alert will be issued. 
 
LL MODULATION BACKUP SENSOR: 
DISABLE, LEAD OUTLET, SLAVE OUTLET 
AVERAGE 
If the sensor chosen by the LL Modulation 
sensor 

is faulty then the backup sensor 

provided here may be used. 
 
If  Disable  is selected then no backup will be 
used. 
 
If  Lead Outlet is selected then the outlet 
temperature of the lead boiler will be used as the 
backup during firing. 
 
If  Slave Outlet Average is selected then 
average of the outlet temperatures of all slave 
boilers that are firing will be used as a backup. 
When the burner demand is off and no burners 
are firing then, for either Lead Outlet or  Slave 
Outlet Average

, the lead boiler's outlet 

temperature is used to monitor for burner 
demand. 
 
Setpoints 
 
LL CH SETPOINT SOURCE: LOCAL, S2 4-
20MA 
If the setpoint source is Local  then the Sola 
control's local setpoint system is used. This 
setting enables the normal use of the CH 
setpoint, CH TOD setpoint, and the CH outdoor 
reset parameters and functions. 
 
If the setpoint source is S2 4-20mA then the 
setpoint is determined by the 4-20mA input on 
S2, and the two parameters described below. If 
the 4-20mA signal goes out of range or is 
invalid, and this persists for a specified time, 
then the setpoint source reverts to "Local". In 
this case once it has gone to "Local", it remains 

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