Honeywell SV2 Series User Manual page 99

Fig. 55: Load Saved Curves.
Base Curve Setup
In case no Base Curve has been loaded to the SV2 Series valve, a Base Curve needs to be created, which sets the amplification as
a function of the appliance load. Refer to
The Base Curve is usually defined in the OEM laboratory for a specific appliance type and capacity. The Base Curve defines
the amplification setting as a function of the measured combustion airflow (excess air levels) over the modulation range of the
system.
NOTE: The valve must be powered for 1 hour in order for the embedded FARMOD heater to effectively warm up the device.
If the full hour is not provided, the programmed lambda and the excess air values might vary from the desired
values.
Fine-tuning of the system for a specific valve, application/burner and location is done via the Correction Curve (refer to the next
section).
The Base Curve can have up to 25 load points distributed over the modulation range of the appliance and be shaped to give
the desired CO2/O2 content in the combustion products over the modulation range (via individual amplification settings). The
curve should be recorded in the laboratory and can be saved to the hard HMI or PC Tools disk/memory for reuse on other valves
on identical appliances (i.e. same valve type, size, mixer, heat exchanger and combustion air supply circuit).
The amount of required setpoints depends on appliance-specific requirements.
The Base Curve makes it possible to have a versatile amplification setting over the modulation range of the appliance without
the need of commissioning more than four points in the field or during production. The shape of the Base Curve is corrected
by the correction values set in the Correction Curve (refer to
defined correction points is found through linear interpolation.
SV2 Series Safety Shut-off Valves
V2F, V2V
Fig. 56.
Fig. 57); the correction values for modulation levels between the
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SV2 SERIES SAFETY SHUT-OFF VALVES USER MANUAL