Operating Position; Modulating; Multistage Operation - Siemens LMV51 Series Basic Documentation

Operating position

Modulating

Note

Multistage operation

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Modulating operation is possible for both types of fuel, gas and oil.
In the operating position, the dampers are driven to the defined fuel / air ratio curves in
accordance with the required output. Up to 15 curvepoints can be defined. The spacing
of the points (difference in output) can be freely selected.
The positions of the breakpoints are calculated by making linear interpolations.
To ensure correct fuel / air ratio control at any time, the actuators travel in steps of
maximum 1.2 seconds. This traveling time corresponds to a positioning angle of 3.6° at
an operating ramp of 30 seconds / 90 °.
For each of these steps, an individual speed is calculated for each actuator, so that all
actuators reach the required positions at the same time.
The speed of the fastest actuator can be parameterized.
Parameter: OperatRampMod
The ® position check is always made between the individual steps when the actuators
do not move.
If there is a breakpoint on the way to the next target on the curve, it will always be
approached.
When parameterizing the operating ramp, the speed of the slowest actuator must be
taken into consideration!
Multistage operation is only possible when firing on oil. It is possible to parameterize if
multistage or modulating operation is used.
Electronic fuel / air ratio control can be configured for both 2-stage and 3-stage burners.
In this operating mode, the oil actuator is not controlled.
Parameter: Operation Mode (Two-stage / Three-stage / Modulating)
Multistage fuel / air ratio control is defined via different load points. These are the
stationary operating points and separately adjustable switch-on / off points.
Parameter: SetPointStage1
Parameter: StartPointStage2
Parameter: OffPointStage2
Parameter: SetPointStage2
Parameter: StartPointStage3
Parameter: OffPointStage3
Parameter: SetPointStage3
Pos.
7550d02E
S1
Multistage operation (here: 2-stage)
Basic Documentation LMV51...
4 Fuel / air ratio control (FARC)
S2on S2off S2
Load
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29.05.2002
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