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Chapter 4. Using Special Features
52
Model PM880 Portable Hygrometer User’s Manual
4.6 Using Automatic Calibration (AutoCal)
The PM880 automatically calibrates the moisture and pressure
measurement circuitry (AutoCal) at a user-selected interval. Autocal
compensates for any drift in the electronics. GE recommends setting the
AutoCal interval to 8 hours. Set a smaller AutoCal interval more frequently
if the meter is exposed to extreme temperatures or weather conditions.
Note:
If you are using only Moisture Image Series (MIS) probes to measure
moisture, the System Menu is not available.
Use the steps below to enter an AutoCal interval:
1.
If the menu is not active, press
[MENU]
.
2.
Use the arrow key to scroll to
Program
and press
[ENTER]
.
3.
Use the arrow key to scroll to
System
and press
[ENTER]
. A screen
similar to Figure 21 appears.
Figure 21: System Configuration Window