
User's Manual
Hygro-Thermometer Pen
Models 445580 and 445582 (kit)
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METER DESCRIPTION
1. Humidity/Temperature Sensor
2. POWER ON/OFF button
3. Data HOLD button
4. MIN/MAX Memory button
5. Calibration and units select button
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6. Memory Reset button
7. Humidity Display
8. Temperature Display
9. Function Displays
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INTRODUCTION
Congratulations on your purchase of the Extech Hygro-Thermometer Pen. This portable
meter can measure Relative Humidity from 10% to 90% and Temperature from 14 to 122
(0 to 50
Display Hold, and Automatic Power Off. The Model 445582 kit includes Relative Humidity
Calibration bottles and hard shell carrying case.
o
C). Advanced features include MIN/MAX Memory, Push-button Calibration,
SPECIFICATIONS
Relative Humidity Sensor High Precision thin-film capacitance type
Temperature Range 14 to 122oF (-10 to 50oC)
Relative Humidity Range 10 to 90% Relative Humidity
Resolution Temperature: 0.1o; Relative Humidity: 0.1%
Accuracy* Temperature: ±1.8oF (±1.0oC); Relative Humidity: ±5%
DC Power 2032 button battery (150 hour battery life)
Response time 120 seconds
Dimensions 6.9 x 1.6 x 0.6" (175 x 42 x 16mm)
* Accuracy applies to the temperature range 32 to 122oF (0 to 50oC)
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OPERATION
Measurements
Press the ON/OFF button to turn the meter ON. After a 5 second initialization, the Relative
Humidity reading will appear in the upper display and the Temperature reading will appear
in the lower display. Allow time for measurement readings to stabilize when moving the
meter from one area to another.
Error Messages
An error message will appear on the display if the meter fails an internal diagnostic test.
E2: Calibration error. Recalibration is necessary.
E5: Relative Humidity sensor failure. Repair/replacement is necessary.
Data Hold
1. Press the HOLD button to freeze the displayed reading. The display icon ‘HLD’ and the
held reading will appear on the display.
2. To return the meter to the normal operation mode, press and hold the RESET button
until the ‘HLD’ icon switches off.
MIN/MAX Memory Recall
1. Press and hold the MIN/MAX button until ‘MIN’ appears in the display. The reading will
then represent the lowest humidity and temperature measurements recorded since the
meter was turned on or last reset.
2. Press and hold the MIN/MAX button until the ‘MAX’ appears on the display. The
reading will then represent the highest humidity and temperature measurements
recorded since the meter was turned on or last reset.
3. Press the MIN/MAX key again to return to normal operation.
MIN/MAX Memory Reset
To reset (clear) the MIN/MAX memory, press and hold the RESET button until ‘88.8’
appears in the display.
Automatic Power Off (Sleep mode)
The meter will automatically shut off after a period of approximately 20 minutes. To defeat
this mode, press and hold the MIN/MAX button while turning the meter on. Release the
ON/OFF button after the display initializes. 'n' will appear on the display indicating that the
non-sleep mode has been activated. Sleep mode will be re-activated when the meter is
turned off however.
Setting Temperature Units (C or F)
Caution: Follow this procedure carefully. Accidentally pressing the RESET button during
this procedure will compromise the meter's calibration.
1. Ensure that the meter is off.
2. Press and Hold
press the ON/OFF button. The unit will power up and the display will flash once. When
only the ‘F’ and ‘C’ icons appear together in the display, release the F/C button.
3. The display will then show either ‘C’ or ‘F’. Press the MIN/MAX key to select degrees
‘C’ or ‘F’. The display will reflect the change.
4. Press the recessed F/C button to store the selection. ‘S’ will appear in the display.
5. The display will then show ‘%MIN’. Turn off the meter to complete the operation.
the recessed F/C button (use a paper clip or similar object) and then
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Models 445580 & 445582 Version 3.2 August 2003