Bosch SSB1000 TL - Cascade Error Handling

SSB 6720892984 (2019/02) US
BURNERS cascade | 17
3.3.6 Cascade – burner rotation (Rev. 4.0.905.x)
The burner rotation function can change the start/stop sequence for the
cascade burners.
The parameter
Burner_Rotation_Interval sets the number of days
after which the sequence is updated.
When
Burner_Rotation_Interval is set to 0 burner rotation is
disabled.
When the parameter
Burner_Rotation_Interval is updated
the burner rotation days left will be initialized to the new
Burner_
Rotation_Interval
setting.
When for example
Burner_Rotation_Interval = 5 the start sequence
is as following (x is the last burner):
Days Start/Stop sequence
Day 0-5 1-2-3-4-5..x
Day 5-10 2-3-4-5..x-1
Day 10-15 3-4-5..x-1-2
Day 15-20 4-5..x-1-2-3
Day 20-25 5..x-1-2-3-4
With parameter First_Depending_To_Start the current depending
that is rst to start in the sequence is selected.
When the burners are rotated the parameter
First_Depending_To_
Start
is automatically updated to the next depending.
When burner rotation is disabled the parameter
First_Depending_
To_Start
is reset to 0.
When the
First_Depending_To_Start is manually changed the
control will clear all demand of the cascade control. After this it will
start cascade demand generation with the new selection for
First_
Depending_To_Start
.
Relevant variables
Specic Parameters Level
(Default)
Value
Range
Burner_Rotation_Interval 2: Installer 5
0..30
0 = Disable
First_Depending_To_Start 2: Installer 1 1..8/16
3.3.7 Cascade – error handling
3.3.7.1 Emergency mode
Open / Shorted boiler or system sensor
When the setting “
Permit_Burner_Emergency_Mode ” is enabled
the control can go into emergency mode when the system sensor status
is not ok. When the system sensor is open or shorted the control goes
into the emergency mode.
The managing burner display may show that the system is in emergency
mode.
In emergency mode the system setpoint is set to the
Cascade_
Emergency_Setpoint
(settable via installer menu).
When an emergency heat demand is generated all burners are allowed to
start burning on this setpoint.
Loss of cascade communication (Rev. 3.0.0.14038)
The leading board is aware of how many dependents should be present
in the system. This value is stored in the e2prom. When powering on the
system the leading burner has to detect all depending burners within 60
seconds.
When not all dependent burners are detected the control will show the
CC_LOSS_COMMUNICATION warning.
When the communication with any of the depending burners is lost during
operation the control will show the
CC_LOSS_COMMUNICATION warning after 60 seconds.
The
CC_LOSS_COMMUNICATION warning is purely informative and will
not block the control.
3.3.7.2 Managing burner error (Rev. 3.0.0.11748)
When the managing burner is in error mode this burner is not used
anymore for the cascade system.
However depending on the error code, the pumps connected by the
managing burner still can be active for the cascade system. When the
managing unit is reset from lockout state, the cascade controllers are
re-initialized.