RH490 Datasheet, PDF (5/7 Pages) Extech Instruments Corporation. – Precision Hygro-Thermometer

Dew Point
1. To select the Dew Point measurement, press the
“°F/°C/WBT/Dew Point” button until DEWPOINT
(°F or °C) appears in the lower right.
2. Dew Point temperature is now displayed.
Wet Bulb
1. To select the Wet Bulb measurement, press the
“°F/°C/WBT/Dew Point” button until WET BULB
(°F or °C) appears in the lower right.
2. Wet Bulb temperature is now displayed.
Temperature
1. To select the temperature measurement, press the
“°F/°C/WBT/Dew Point” button until “°C” or “°F”
appears in the lower right.
2. Temperature is now displayed.
Data Hold
1. Press the ”H MAX MIN” button momentarily to
freeze the displayed readings. ”HOLD” will appear
on the upper left-hand side of the display.
2. Press the ”H MAX MIN” button three more times to
return to normal operation. (Steps through MAX
and MIN)
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RH490 V2.0 12/06