Campbell CR3000 Micrologger, Руководство оператора

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Section 7. Installation
239
a. For the first point, set variable SimulatedFlowSignal
=
300. Set variable
KnownFlow
=
30.0.
b. Start the calibration by setting variable CalMode
=
1.
c. When CalMode increments to 3, for the second point, set variable
SimulatedFlowSignal
=
550. Set variable KnownFlow
=
10.
d. Resume the deployment calibration by setting variable CalMode
=
4
4. When variable CalMode increments to 6, the deployment calibration is
complete. Calibrated multiplier is -0.08; calibrated offset is 53.9.
5. To continue this example, suppose the simulated sensor multiplier and offset
drift. Simulate a seven-day service calibration to correct the drift as follows:
a. Set variable SimulatedFlowSignal
=
285. Set variable KnownFlow
=
30.0.
b. Start the seven-day service calibration by setting variable CalMode
=
1.
c. When CalMode increments to 3, set variable SimulatedFlowSignal
=
522. Set variable KnownFlow
=
10.
d. Resume the calibration by setting variable CalMode
=
4
6. When variable CalMode increments to 6, the calibration is complete. The
corrected multiplier is -0.08; offset is 53.9.
FieldCal() Two-Point Slope and Offset
'This program example demonstrates the use of FieldCal() in calculating and applying a
'multiplier and offset calibration. A multiplier and offset calibration compares signal
'magnitudes of a sensor to known standards. The calculated multiplier and offset scale the
'reported magnitude of the sensor to a value consistent with the linear relationship that
'intersects known points sequentially entered in to the FieldCal() KnownVar parameter.
'Subsequent measurements are scaled by the new multiplier and offset.
'This program demonstrates the multiplier and offset calibration with the following procedure:
' -- Simulate a signal from a flow sensor.
' -- Measure the 'sensor' signal.
' -- Calculate and apply a multiplier and offset.
'You can set up the simulation by loading this program into the CR3000 and interconnecting
'the following terminals with a jumper wire to simulate a flow sensor signal as follows:
' Vx1 --- SE 1
'For the simulation, the value of the calibration standard and the initial 'sensor' signal
'are set automatically. Start the multiplier-and-offset routine by setting variable
'CalMode = 1. The value in CalMode will increment automatically. When CalMode = 3, set
'variables SimulatedFlowSignal = 550 and KnownFlow = 10, then set CalMode = 4. CalMode
'will again increment automatically. When CalMode = 6 (occurs automatically after 10