Fluke RUSKA 7050, Руководство пользователя

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Theory of Operation
Software
2
2-9
2-6.bmp
Figure 2-6. Menu | Display-Menu
Pressure Reading and Correction
The sensor’s analog output is processed by an analog-to-digital circuit that results in an
output referred to as counts. This output is corrected for the applied effects listed below.
The counts are linearized and the resulting pressure value is corrected for the variations in
head pressure, vacuum, case effect, and oven temperature effects.
The following equations are used by the control algorithm to adjust and correct the
pressure signal.
Zero Coefficients
CsH Zero correction for High FSR (Full-Scale Resistors) Value is in counts
(7,381,975 = full scale of current sensor).
CsL Zero correction for Low FSR. Value is in counts (7,381,975 = full scale
of low FSR)
HsZ Hardware zero correction. (0 to 4095, center is 2048).
SsZ Zero corrections scaling factor. Ratio of High FSR to Low FSR. Used only when
Case Effect Coefficient or Oven Temperature Coefficient are non-zero.
s=0 for high range sensor, s=1 for low range sensor.
Range Coefficients
KnF 0=Range Unused
4=Valid High FSR Range
5=Valid Low FSR Range
Kn0, Kn1, Kn2 Calibration constants for range
0
24
1
2
48
2 *
2
*
2
n
n n K A
K
A
K
B
+ + =
Where A is the zero corrected counts (7,381,975 = full scale of current range) and
B is the calibrated counts (7,381,975 = full scale of current sensor)