CALIBRATION 2. F/C Switching User can select °C or °F as the temperature mode by press ing for temperature more than 1 sec. during Self-Test. 3. Alarm Setting The meter is preset at the alarm value of 25 ppm to give warnings of possible danger. Users can adjust the value for different needs or standard by: 1. Turn off the meter. 2. Press and hold Ф until the value options show. There will be 25, 30, 35, 45, 50, 70, 100, and 200ppm display ing in cycles. 3.
