GE PM880, Руководство пользователя

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Chapter 8. Maintenance and Troubleshooting
Model PM880 Portable Hygrometer User’s Manual 161
8.14Recalibrating the Pressure Sensors
Since the pressure sensor on a TF Probe or on Moisture Image Series (MIS)
Probes is a strain gage type, the pressure calibration is linear and is
calibrated at 2 data points. Each point consists of a voltage or FP value and
a corresponding pressure value in psig. Check or change the two calibration
data points using the steps below.
1.
Set one of the boxes on the screen to display pressure in mV (or FP) and
another box to display psig. Refer to
Displaying Measurements on
page 15 to set up the screen.
2.
Expose the pressure sensor to air and record the mV (or FP) and psig
readings. This reading is for the zero pressure.
3.
Expose the pressure sensor to a known full scale pressure source and
record the mV (or FP) and psig readings. This reading is for the span
pressure.
4.
Press [MENU] .
5.
Use the arrow key to scroll to Program and press
[ENTER]
.
6.
Use the arrow key to scroll to
Calibration
and press [ENTER] .
7.
Proceed to Entering Pressure Calibration Data on page 14 to complete
entering data.