General Tools & Instruments EP8703 Instruction Manual

CALIBRATABLE

3-FUNCTION

PSYCHROMETER

USER’S MANUAL

EP8703

Please read this manual carefully and

thoroughly before using this product.

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . 2 – 3

Key Features . . . . . . . . . . . . . . . . . . . . 4

What’s in the Box . . . . . . . . . . . . . . . . 4

Product Overview . . . . . . . . . . . . . 4 –6

Setup Instructions . . . . . . . . . . . . 6 –7

Install Battery . . . . . . . . . . . . . . 6 –7

Operating Instructions . . . . . . . . . 7 –8

Making Basic Measurements . . 7 –8

Calibrating the Meter . . . . . . . . . 8 – 12

Specifications . . . . . . . . . . . . . . . . . . 13

Operating & Maintenance Tips . . . . . 14

Warranty Information . . . . . . . . . . . . 15

Return for Repair Policy . . . . . . . . . . 16

INTRODUCTION

Thank you for purchasing General Tools
& Instruments’ EP8703 Calibratable
3-Function Psychrometer. Please read this
user’s manual carefully and thoroughly
before using the instrument.

The EP8703 can measure any
environment’s ambient temperature,
relative humidity (RH) and dew point. These
measurements are typically made by three
groups of users:

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• 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 EP8703 is powered by one “9V” battery
(included).

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KEY FEATURES

• Jumbo backlit display with 2-line readout

• Field calibratable using optional 33% and
75% salts

• °F/°C switch

• 20-minute Auto Power Off function

• Low battery indicator

WHAT’S IN THE BOX

The EP8703 comes fully assembled in a box
along with a sensor protection cap, a “9V”
battery and this user’s manual.

PRODUCT OVERVIEW

Figure 1 shows all of the controls, indicators
and physical structures on the front, top and
bottom of the EP8703. Figure 2 shows all
text and icons that could appear on the
unit’s LCD. Familiarize yourself with the
positions and functions of all buttons,
structures and icons before moving on to
the Setup Instructions and Operating
Instructions.

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A

B

F

Fig. 1. The EP8703’s controls, indicators
and physical structures

A. Humidity and temperature sensors
B. LCD
C. (Power on/off) button
D.

F/C

button
E. Battery compartment
F.

DEW

button

C
D

E

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