Extech Instruments 445703 User manual

1445703 Ver. 1.6 06/00
INSTRUCTION MANUAL
Model 445703
Big Digit Hygro-Thermometer
•Displays temperature and relative humidity
•Selectable temperature units oC/oF
•MIN/MAX memory and recall
•For wall-mount or desktop use
1. INTRODUCTION
Congratulations on your purchase of Extech’s Big Digit Hygro-Thermometer. This
professional meter, with proper care, will provide years of safe reliable service.
2. SPECIFICATIONS
Range Accuracy
Temperature -10 to 60oC
14 to 140oF+1.0oC within -10oC to 50oC +1.8oF within 14oF to 122oF
Humidity 10% to 99% +5% RH within 25% to 85% RH and
0 to 50oC or 32 to 122oF
Battery 1.5V 'AAA' cell

2445703 Ver. 1.6 06/00
3. OPERATION
1. Open the battery compartment by pushing the cover on the rear of the instrument
downward as indicated by the arrow. Remove the battery safety strip and the
protective cover on the LCD display. The instrument is now ready for use.
2. The temperature units can be selected via the switch located on the rear of the
instrument.
3. The upper display indicates the temperature in degrees C or F. The lower display
indicates relative humidity in %.
4. Displaying the minimum and maximum values.
a. Press the MAX/MIN button. The highest value measured since the Reset button
was last pressed appears on the display.
b. Press the MAX/MIN button again to display the lowest value measured since the
Reset button was last pressed.
c. Press the MAX/MIN button again to return to normal display operation.
5. Resetting (clearing) the MAX/MIN memory.
a. Press and hold the RESET button for 1 second while in the MAX/MIN display
mode to clear the memory and start recording new max/min values.
6. The unit can be wall-mounted or placed on a flat surface using the fold-out footing.
7. The low battery flag will appear on the display when the battery voltage is low.
Replace the battery when this occurs.
4. BATTERY REPLACEMENT
Open the battery compartment by sliding the battery cover on the rear of the instrument
downward as indicated by the arrow . Replace the 1.5V ‘AA’ battery and replace the cover.
5. CALIBRATION / REPAIR SERVICES
Extech offers complete repair and calibration services for all of the products we sell. For
periodic calibration, NIST certification or repair of any Extech product, call customer
service for details on services available. Extech recommends that calibration be performed
on an annual basis to insure calibration integrity.
6. WARRANTY
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and
workmanship for one year from date of shipment (a six month limited warranty applies on sensors and
cables). If it should become necessary to return the instrument for service during or beyond the warranty
period, contact the Customer Service Department at [phone] ext. 210 for authorization. A Return
Authorization (RA) number must be issued before any product is returned to Extech. The sender is
responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit.
This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring,
operation outside of specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific purpose and will not
be liable for any direct, indirect, incidental or consequential damages. Extech's total liability is limited to
repair or replacement of the product.
The warranty set forth above is inclusive and no other warranty, whether written or oral, is expressed or
implied.
Copyright ©1999 Extech Instruments Corporation. All rights reserved
including the right of reproduction in whole or in part in any form.