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An auto power off facility turns the Therma-Hygrometer off automatically after 20 minutes which maximises battery life. The unit is powered by a 9 volt alkaline PP3 battery with a minimum life expectancy of up to 100 hours or via a 9/230 volt AC/DC power adaptor for continuous use.

The Therma-Hygrometer probe is detachable via a 6-pin connector, however if the probe requires replacement, the instrument will require recalibration. Supplied complete with carrying case, battery and instructions for use. RH calibration test capsules are available for 33% and 75% RH (supplied as a pair).

Model / Temperature / Humidity
Range/ 0 to +90°C / 0 to 100% RH
Resolution / 0.1°C or °F / 0.1% RH
Accuracy / ±0.5°C ±1 digit / ±3% (15 to 90% RH)
Sensor Type / Semi conductor / Thin film polymer 
Battery / 9 volt MN1604/PP3
Battery Life / Approximately  100 hours
Display / 12.7mm LCD
Dimensions / 147 x 80 x 36mm
Weight / 210 grams

Order Code / Description
225-060 / 8711 Therma-Hygrometer
816-075 / RH 8711 Therma-Hygrometer
825-200 / RS232 Lead & Software
812-002 / 9/230 volt AC/DC Power Adaptor
825-210 / Protective Boot

8703 Therma-Hygrometer
This easy to use pocket sized ETI 8703 Therma-Hygrometer measures both relative humidity and air temperature and calculates dew point. The Therma-Hygrometer incorporates a clear LCD display indicating both RH and temperature simultaneously. There is an automatic display of both 'Open Circuit' and 'Low Battery' and '°C/°F', '% RH', 'Max/Min' and 'Hold' functions. The ETI 8703 Therma-Hygrometer is powered by two 1.5 volt alkaline MN2400 (AAA) batteries which allow the unit to operate up to 500 hours or one year. The unit is supplied with a sensor protective cover which incorporates a pocket clip. 

Specification / Temperature /  Humidity
Range / -10 to +50°C / 5 to 95% RH
Resolution / 0.1°C or °F / 0.1% RH
Accuracy/ ±1°C ±1 digit / ±3% (10 to 90% RH)
Sensor Type / Thermistor / Capacitance
Battery / 2 x 1.5 volt MN2400 (AAA)
Battery Life / Approximately 500 hours
Dimensions / 17 x 48 x 170mm
Weight / 100 grams

Order Code / 816-703

Mason's Hygrometer
The Mason's hygrometer is a wall-mounted wet and dry thermometer for determining the relative humidity. The hygrometer measures the wet and dry temperature over the range of -10 to +50°C enabling the relative humidity to be calculated (1 to 97% RH). The unit is supplied with a slide rule for calculating the relative humidity. The unit is manufactured from a robust blue ABS plastic and measures 40 x 80 x 310mm.

Order Code / Description
817-060 / Mason's Hygrometer - Blue

Mason's Hygrometer
The Mason's hygrometer is a wall-mounted wet and dry thermometer for determining the relative humidity. The hygrometer measures the wet and dry temperature over the range of -15 to +50°C enabling the relative humidity to be calculated (1 to 97% RH). The unit is supplied with a slide rule for calculating the relative humidity. The unit is manufactured from a robust white ABS plastic and measures 34 x 75 x 310mm.

Order Code / Description
817-050 / Mason's Hygrometer - White

Pocket Whirling Hygrometer
This pocket whirling hygrometer (sling psychrometer) is a reliable instrument for the measurement of relative humidity utilising wet and dry bulb spirit-filled thermometers. The handy self-contained case folds into a compact pocketable size. The hygrometer measures the wet and dry temperature over the range of 0 to +45°C enabling the relative humidity to be calculated (1 to 97% RH). The unit incorporates an integral slide rule for ease of reading and convenience.

Order Code / Description
817-010 / Pocket Whirling Hygrometer

Professional Whirling Hygrometer
<span lang="EN-GB" style="font-size: 10.0pt; font-family: Verdana">This professional whirling hygrometer (sling psychrometer) offers the maximum level of accuracy for the measurement of relative humidity utilising wet and dry bulb mercury-filled thermometers. The hygrometer is housed in a robust yellow plastic frame with a blue handle. The instrument incorporates a small water reservoir linked to the wet bulb by the means of a cotton sleeve. The thermometer tubes measure temperature over the range of 0 to +50°C enabling the % RH to be calculated utilising the chart supplied.

Order Code / Description
817-001 / Professional Whirling Hygrometer
817-025 / Spare Tubes

Digital Hygro-Thermometer
This digital hygro-thermometer features an easy to read dual display, simultaneously displaying both temperature and humidity. The compact and cost-effective hygro-thermometer will indicate and record maximum and minimum readings of both temperature and humidity over the range of -20 to +70°C and 20 to 99% RH. The instrument also features a high/low audible alarm. The instrument is powered by a single MN2400 (AAA) battery with a life expectancy of 1,000 hours. 

Order Code / Description
810-155 / Digital Hygro-Thermometer