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Siemens Building Technologies  Basic Documentation LMV5...  CC1P7550en 
HVAC Products  5 Fuel / air ratio control (FARC)  13.08.2004 
 
 
Parameters:  LMV51...  LMV52...   
       
AuxActuator (deactivated / activated)  x  x   
VSDOperation  LMV51.2...     
AirActuator (deactivated / activated) (air influen)    x   
AuxActuator 1 (deactivated / activated) (air influen)    x   
AuxActuator 2 (deactivated / activated) (air influen)    x   
AuxActuator 3 (deactivated / activated) (air influen)    x   
VSD (deactivated / activated)(air influen)    x   
 
If the auxiliary actuator is not required, it must be deactivated. This can be selected 
separately for both types of fuel. Here, with the LMV51.2..., the VSD will be activated. 
 
The required actuators must be activated. If O2 trim control is used, the actuators hav-
ing an impact on the air volume must be parameterized to «air influen». 
 
The standard LMV5... system uses 1 fuel actuator for gas and 1 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 ad-
dressed 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 an-
gular 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 facili-
tate 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. 
 
Activation of 
actuators / VSD 
LMV51... 
LMV52... 
Number of fuel actuators 
Note 
Traveling times 
Shutdown behavior 
Overload protection 
of actuators 
Curve adjustment