Operation; Powering The Meter; Max/Min/Avg Memory; Data Hold - Extech Instruments RH25 User Manual

Operation
Keypad
POWER: Switch the meter ON or OFF; also used to enter the MAX/MIN/AVG memory mode.
HOLD: Press to enter Data Hold (reading freezes on display). Press again to exit Data Hold.
MODE: Press to step through the measurement modes: TEMP (Temperature), RH (Relative
Humidity), HI (Heat Index), DP (Dew Point), (WB (Wet Bulb), and HI/WB (Wet Bulb Globe).
Powering the meter
Press POWER to switch meter ON. The meter shows all display icons momentarily as it switches
ON and then the TEMP icon and the temperature reading will display. The meter will also emit a
chirp sound as it switches ON.
To switch the meter OFF, press and hold the POWER button for at least 2 seconds.
MAX/MIN/AVG Memory
With the meter powered ON, press POWER button momentarily. The MAX icon will appear and
the meter will display only the highest reading.
Press POWER again; the MIN icon will appear and the meter will only display the lowest reading.
Press POWER again; the AVG icon will appear and meter will only display the average reading.
Press POWER again to exit (the MAX/MIN/AVG icons will switch OFF).
Data Hold
With the meter powered ON, press the HOLD button momentarily. The HOLD icon will appear
and the current reading will freeze on the display. Press HOLD again to exit (the HOLD icon will
switch OFF).
Automatic Power OFF (Sleep) Mode
The meter switches OFF automatically after 15 minutes of inactivity. To defeat this feature
temporarily: With the meter switched OFF, press the HOLD and POWER buttons simultaneously
until the meter displays the screen shown below. Now, the user must switch the meter OFF
manually by pressing and holding the POWER button for at least 2 seconds. Note that the next
time the meter's power is cycled, the Auto Power OFF utility will again be active.
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