Number Of Fuel Actuators; Traveling Times; Shutdown Behavior; Overload Protection Of Actuators - Siemens LMV51 Series Basic Documentation

Number of fuel actuators

Note

Traveling times

Shutdown behavior

Overload protection
of actuators

Curve adjustment

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The standard LMV51... system uses one fuel actuator for gas and one fuel actuator for
oil. But it is also possible to use one common actuator for the fuel damper and the oil
pressure controller.
However, it is still possible to parameterize independent curves for both types of fuel.
Parameter: NumFuelActuators (1 / 2)
If the above mentioned parameter was set to «1», the common fuel actuator must be
addressed as a «gas actuator».
The traveling speed of the actuators can be adjusted for the different burner statuses.
The time to be parameterized is the period of time the actuator requires to cover an
angular rotation of 90°.
Traveling speed in the phases with no flame (e.g. traveling to prepurge):
Parameter: TmeNoFlame
Traveling speed in the operating position in modulating operation:
Parameter: OperatRampMod
Traveling speed in the operating position in multistage operation:
Parameter: OperatRampStage
When parameterizing the speeds, the running times of the connected actuators must be
taken into consideration.
The positions the actuators assume in the event of lockout can be adjusted. To facilitate
fault diagnostics, the actuators can be stopped at their last position or can be driven to
their home or postpurge position.
Parameter: ShutdownBehav (Unchanged / PostpurgeP / HomePos)
If the actuators block, lockout will be enforced.
However, if the actuators cannot reach the positions required by lockout, they would be
damaged due to overtemperatures.
To prevent this, the actuators will be deactivated after a maximum time of 35 seconds,
or at 20 % above the value for TmeNoFlame parameterized.
Refer to chapter «Displays and settings» / special function curve adjustment FARC.
Basic Documentation LMV51...
4 Fuel / air ratio control (FARC)
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CC1P7550en
29.05.2002