background image

• Water damage restoration contractors

• HVAC/R system installers and technicians

• Professionals charged with monitoring

and maintaining the environment of
facilities such as office buildings,
greenhouses, food and equipment storage
facilities, wineries, freezers, shipping
containers, computer rooms, labs,
libraries, museums and saunas.

The dew point is the temperature below
which the water vapor in a volume of air at
a given constant barometric pressure will
condense into liquid water at the same rate
at which it evaporates. Condensed water is
called dew when it forms on a solid surface.

Another way to think of the dew point is as
an air saturation temperature associated
with relative humidity (RH). A high RH value
indicates that the dew point is close to the
current ambient air temperature. At 100%
RH, the dew point temperature is equal to
the ambient temperature because the air is
completely saturated with water.

The wet bulb temperature is the
temperature that a volume of air would
have if it were cooled to saturation (100%
RH) by the evaporation of water into it, with
the latent heat coming from the volume of
air. It is the lowest temperature that can be
reached under current ambient conditions
by the evaporation of water only. The wet

3

Summary of Contents for EP8709

Page 1: ...O HYGROMETER USER S MANUAL EP8709 Please read this manual carefully and thoroughly before using this product 99 Washington Street Melrose MA 02176 Phone 781 665 1400 Toll Free 1 800 517 8431 Visit us...

Page 2: ...Operating Maintenance Tips 14 Warranty Information 15 Return for Repair Policy 16 INTRODUCTION Thank you for purchasing General Tools Instruments EP8709 Calibratable 4 Function Thermo Hygrometer Plea...

Page 3: ...Condensed water is called dew when it forms on a solid surface Another way to think of the dew point is as an air saturation temperature associated with relative humidity RH A high RH value indicates...

Page 4: ...tch 20 minute Auto Power Off function Low battery indicator WHAT S IN THE BOX The EP8709 comes fully assembled in a box along with a sensor protection cap a 9V battery and this user s manual PRODUCT O...

Page 5: ...ndicators and physical structures A Humidity and temperature sensors B LCD C Power on off button D F C button E WBT wet bulb temperature button F DEW button G HOLD button H MAX MIN button I Battery co...

Page 6: ...w battery icon B Data hold indicator C Maximum reading indicator D Minimum reading indicator E C indicator F F indicator G Wet bulb temperature indicator H Dew point temperature indicator I Temperatur...

Page 7: ...et inside the compartment The terminals of the battery and the socket mate in only one way with the smaller male terminal plugging into the larger female terminal 3 Replace the battery compartment cov...

Page 8: ...ding will be accompanied by the symbol WBT at its left To return to displaying ambient temperature press the WBT button again By default the EP8709 displays ambient dew point and wet bulb temperatures...

Page 9: ...power off the EP8709 press and hold the button for at least 3 seconds TRACKING MIN AND MAX LEVELS After being powered on the EP8709 automatically operates in Recording mode for the purpose of tracking...

Page 10: ...eadout Exiting Min Max mode clears the Min Max memory and begins a new measurement session CALIBRATING THE METER Your EP8709 was calibrated at the factory so its measurements should remain within thei...

Page 11: ...ction disabled rotate the sensor protection cap to open its three vents and expose the humidity sensor to the environment 2 Press and hold the DEW and F C buttons at the same time and then release the...

Page 12: ...s cap The fit should be tight with no air leaking into the bottle 7 Leave the meter upside down in the 75 salt bottle for at least 40 minutes The calibration to 75 is fully automatic and requires no...

Page 13: ...RH Measurement Accuracy 3 from 5 to 95 RH RH Measurement Resolution 0 1 Response Time 80 seconds Display Size 1 7 in 43mm diagonal Current Consumption 15mA Battery Life 60 hours typical Dimensions of...

Page 14: ...and temperature sensors after each measurement session rotate the sensor protection cap to close its three vents Do not operate the EP8709 in the presence of a flammable or explosive gas or near an ar...

Page 15: ...ttempted repair by non authorized personnel or misuse alterations normal wear and tear or accidental damage The defective unit must be returned to General Tools Instruments or to a General authorized...

Page 16: ...nter at this address General Tools Instruments 75 Seaview Drive Secaucus NJ 07094 212 431 6100 Remember to include a copy of your proof of purchase your return address and your phone number and or e m...

Reviews: