Siemens LMV5 Series Basic Documentation page 252

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18.4.2 Load limitation with O
O trim control can be deactivated below an adjustable load limit. This can be selected
2
separately for gas- and oil-firing.
Parameter:
O CtrlThreshold
2
If the load drops below this limit, O
operates along the parameterized ratio curves. If the load increases and exceeds the
O trim control threshold by 5 percentage points, the O
2
reinitialized.
18.4.3 Startup
With the parameter setting
Parameter:
O
2Ctrl
startup will be prevented until the O2 sensor has reached its operating temperature.
With the parameter setting
Parameter:
O Ctrl/Guard (conAutoDeac)
2
starts the burner directly, O
temperature has been reached and sensor test has been successful.
Also refer to subsection 18.4.4, Heating up the O2 sensor after «PowerOn».
18.4.4 Heating up the O
When the system or the O2 module is switched on for the first time, the cold O2 sensor
is slowly heated up until its operating temperature is reached. When this temperature is
attained, the sensor requires another 10 minutes for fully assuming that temperature.
With the parameter setting
Parameter:
O Ctrl/Guard (O
2
until the O2 sensor has fully assumed its operating temperature, followed by burner
startup. O trim control in the operating position will be activated the moment the
2
controller locking time has elapsed.
With parameter setting
Parameter: O Ctrl/Guard (conAutoDeac)
2
the burner will immediately be started up. O
only take place when the sensor has fully assumed its operating temperature and after
the sensor test has been successfully completed.
Basic Documentation LMV51...
18 Addendum 4: LMV52... with O2 trim control and O2 module
trim control
2
trim control will be deactivated and the system
2
/Guard (O / O
2-guard 2-control
trim control will be activated only when the operating
2
sensor after «PowerOn»
2
/ O
2-guard 2-c
trim control in the operating position will
2
trim controller will be
2
)
ontrol)start prevention will take place
CC1P7550en
01.10.2003