Campbell CR6 Series, Руководство оператора

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Section 7. Installation
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'PERFORM A MULTIPLIER CALIBRATION.
'Start by setting variable CalMode = 1. Finished when variable CalMode = 6.
'FieldCal(Function, MeasureVar, Reps, MultVar, OffsetVar, Mode, KnownVar, Index, Avg)
FieldCal (3,WC,1,WCMultiplier,0,CalMode,KnownWC,1,30)
'If there was a calibration, store it into data table CalHist
CallTable (CalHist)
NextScan
EndProg
7.7.12.5.5 FieldCal() Zero Basis (Opt 4) Example
Zero basis point calibration loads values into zero-point variables to track
conditions at the time of the zero calibration. The syntax is:
FieldCal (4,Accel,1,0,ZeroState,Mode,0,1,Avg)
When a calibration is performed, the current Accel value is loaded into ZeroState .
Uses for a zero-basis point calibration include applications wherein the result is
based not only on the zero offset for a single sensor, but the zero state of multiple
sensors. For example, a non-vented piezometer whose result should take into
account a zero reading from the sensor as well as the effects due to temperature
and barometric pressure changes with respect to their values at the time of
calibration. Such an equation might look like:
Press = G(R0 – R1) + K(T0 – T1) + (S0 – S1)
Where,
Press = current result in the correct engineering units
G = the sensors gage factor
R0 = the sensor output at the zero state (out of water)
R1 = current output from the sensor
K = the sensors temperature correction coefficient
T0 = The recorded temperature at the time of the zero state
T1 = current temperature measurement result
S0 = The recorded barometric pressure at the time of the zero state
S1 = The current barometric measurement result