User Guide

7
be removed. Whenever the probe is to be
used in a dusty or smoky environment, the
filter must be kept on at all times.
TEMPERATURE MEASUREMENTS
Simply press the °C or °F keys to take the
temperature readings directly from the same
probe.
Note: Press °C key to display
the temperature in °C.
"°C" is displayed when mea-
suring temperature in degrees
Centigrade.
EXAMPLE: A temperature
reading taken in degrees
Centigrade would read:
Press °F key to read the same
value in degrees Fahrenheit:
If you experience any problems in taking
measurements, please contact your dealer or
the nearest Hanna Instruments Customer
Service Department.
°C
°C
°C
°F
°F
6
OPERATIONAL GUIDE
INSTRUMENT PREPARATION
Each meter is supplied complete with a 9V
battery. Slide off the battery compartment
cover on the back of the meter (see page 12),
unwrap the battery and install it.
To prepare HI8564 for use connect the RH
probe to the DIN socket on the top of the meter.
Turn the
meter on by
pressing the
ON/OFF key.
Using the HI8564 or HI93640 thermo-hy-
grometer is simple. However, the recommen-
dations below should always be followed.
RELATIVE HUMIDITY MEASUREMENTS
• The end of the humidity detector should be
exposed to a current of air moving at 0.5 m
(20") per second or more.
• In the absence of air movement, the re-
sponse can be accelerated by moving the
probe.
• The probe sensor must never come into
contact with water or other liquids. If this
should happen, or if condensation causes
drops to form on the surface of the humidity
sensor, turn off the instrument and wait until
the liquid has evaporated completely. In
order to accelerate the evaporation pro-
cess, the humidity sensor could be exposed
to a current of air.
For HI93640 only: in order to obtain a
faster response, the sintered filter should
ON
OFF
ON
OFF