USER GUIDE Wet Bulb Thermo-Hygrometer Datalogger Plus Dew Point Temperature Model WB200
Introduction Thank you for selecting the Extech Instruments WB200 Thermo-Hygrometer Datalogger with Dew Point and Wet Bulb Temperature readings. This device measures and displays four (4) environmental parameters: Air Temperature, % Relative Humidity, Wet Bulb Temperature, and Dew Point Temperature. This meter combines traditional dry/wet bulb operation with modern electronic circuitry providing accurate readings and trouble-free operation especially in dusty environments.
Meter Description 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
Operation Getting started Momentarily, press the Power button to switch the meter ON. After the 3-second power-up self-test, the meter switches to the normal measurement mode where the Air Temperature, % Relative Humidity, Wet Bulb Temperature, and Dew point Temperature readings cycle automatically every two seconds on the LCD (refer to Figure 1 below).
Alarm Mode The WB200 features High and Low temperature and humidity Alarms that alert the user when a reading has exceeded a programmed limit for 30 seconds. The alert switches off when a reading returns to normal for 30 seconds. Refer to SETUP section for details on setting alarm thresholds. When alarming, the LED (located above the LCD) flashes RED and the beeper sounds.
Setup Mode SETUP Mode Overview In the set-up mode, the user can customize the functionality of the meter. To access the set-up mode, press and hold the SET key for 2 seconds. Once in the set-up mode, use the ENTER ( ) key to step through the four (4) available parameter icons and use the up arrow key to change a setting. Each parameter is explained below: ALARM MODE TEMPERATURE (Displayed as t. ON/OFF): High and Low Temp. Alarms ALARM MODE RH (displayed as rh.
2. Relative Humidity Alarm Mode – (rh.ON/OFF) In the RH Alarm mode the user can set the alarms ON or OFF and set the High and Low Alarm Limit values. When the limits are exceeded, the meter audibly and visibly (red flashing LED) alerts the user. Refer to the Operation section of this guide for more details on alarm alerts. a. When the temperature alarm parameters are set as described above and the user presses the ENTER ( ) key to continue, the rh.ON/OFF screen appears. Use the key to change to rh.
Troubleshooting For unusually high humidity readings, check the condition of the cotton wick immersed in the water bottle. Ensure that the cotton wick is kept moist and the water bottle is 80% full.
Water Tank Refilling 1. Open the water tank cover by first gripping the meter with one hand and prying the cover off with the other (pulling forward on the meter’s two side tabs). 2. Remove the water tank from the meter and then remove the tank’s stopper. 3. Refill the water tank to 80% full. The tank capacity is 120ml (4oz.). 4. Replace the tank’s stopper, place the water tank inside the meter, and place the cotton wick into the water tank.
Specifications LCD Display 7-segment digit type for readings and messages Function icons above and below reading for units and mode status Low battery indication LED status indicator Flashes red in an Alarm condition Flashes green when a reading is logged Audible Alert Sounds intermittently when in an Alarm condition Response time 120 second update rate Temperature Units Switchable Temperature units ( C/ F) Measurement ranges Temperature (air, wet bulb, dew point): 5 to 50 C (41 to 122 F) o o
