User's Guide Humidity / Temperature Clock Model 44533 Introduction Congratulations on your purchase of the Extech Humidity / Temperature Clock. This Clock displays Time, Temperature, and % Relative Humidity simultaneously. Proper care and use of this device will provide years of reliable service. Operation 1. Insert one 1.5V 'AA' battery (alkaline batteries are recommended) in the rear battery compartment. Ensure that the (+) positive and (-) minus terminals of the battery match the positive and negative symbols on the clock's battery compartment. Battery life is typically one year. 2. Set the clock hands by rotating the rear knob on the battery compartment. 3. Hang clock in desired location. Description 1. 2. 3. 4. 5. Hanger Temperature adjust Time adjust Battery RH adjust Specifications Time Temperature Relative Humidity 1 2 3 4 12 hour; ± 30 secs per month -40 to 120oF(-40 to 50oC); ± 5oF (± 3oC) 0 to 100% RH; ± 8% 5 Calibration NOTE: The Clock is shipped calibrated. Calibration procedures should only be performed if necessary: Thermometer Calibration The built-in thermometer is very sensitive to changes in air temperature and can be calibrated as follows: 1. Place the clock in a test area where the temperature is known so that you can set the Model 44533 clock temperature to match the test area temperature. 2. Through the adjustment slot on the rear of the clock, gently slide the adjust bar until temperature reading matches the test area temperature. 3. Allow the clock to remain in the test area for 90 minutes to ensure that the clock temperature accurately matches the test area after stabilizing. Adjust again if necessary. Relative Humidity Calibration The built-in Relative Humidity sensor measures indoor relative humidity only. Humidity meters respond slowly to changes in air moisture, when conditions change abruptly it may take up to an hour for the meter to display accurate Relative Humidity. Follow these steps to calibrate humidity: 1. Wrap the clock in a moist piece of linen or cloth for 1 hour. 2. The humidity pointer should read 94 to 96% after 1 hour. 3. Through the adjustment slot on the rear of the clock, gently slide the adjust bar until %RH reading matches the test area RH. Copyright © 2002 Extech Instruments Corporation. All rights reserved including the right of reproduction in whole or in part in any form. www.extech.com [email protected] 44533 V1.0 5/02