7
6
PRELIMINARY OPERATIONS
•
Plug the supplied 12 Vdc adapter into the power supply socket
on the rear panel.
Note:
Make sure the main line is protected by a fuse.
•
Connect the desired probe (
HI
76303
for conductivity or
HI
3316D
for resistivity measurements) to the DIN socket on the rear panel.
The instrument will automatically recognize which probe is con-
nected.
Note:
Make sure that the instrument has been calibrated before
taking conductivity measurements (see “Calibration” section).
Note:
If possible, use plastic beakers to minimize EMC interferences.
•
Switch the meter on by pressing the ON/OFF
key.
TAKING CONDUCTIVITY MEASUREMENTS
•
Immerse the
HI 76303
probe in the solution,
while making sure that the holes of the sleeve
are completely submerged. Tap the probe
lightly on the bottom of the beaker to remove
any air bubbles trapped inside the sleeve.
•
Adjust the conductivity TC knob to the tem-
perature coefficient value of the solution (see
“Determination of the temperature coefficient
of a solution” section for details).
•
Select the appropriate conductivity range, by
pressing the corresponding key.
Note:
If the display shows "1", the reading is
over-range. Select the next higher range.
•
Allow a few minutes for the reading to stabilize, and the LCD will
display the temperature compensated conductivity reading.
OPERATIONAL GUIDE
TAKING RESISTIVITY MEASUREMENTS
•
Immerse the
HI 3316D
probe in the solution,
while making sure that the hole on the probe
body is completely submerged.
• Wait for a few seconds to allow stabilization of
reading. The resistivity value of the solution
will be displayed on the LCD.
Note:
If the display shows "1", the reading is over-range.
• The reading is automatically corrected for temperature variations
by using the linear compensation method:
R
25
=R
t
(1+
β
(t-25))
where R
t
is the resistivity at the temperature t, and the reference
temperature is 25ºC.
• The temperature coefficient
β
is selectable
through a front knob, from 2 to 7%/°C.