
42
The instrument has two temperature channels: one that measures the
temperature from the
HI7662
probe while the instrument is in pH/mV
range and the other that measures temperature from the EC probe while
the instrument is in EC/TDS/NaCl range.
All the instruments are factory calibrated for temperature on both
channels.
Hanna Instruments’ temperature probes are interchangeable and no
temperature calibration is needed when they are replaced.
If the temperature measurements are inaccurate, temperature recalibra‑
tion should be performed.
For an accurate recalibration, contact your local Hanna Instruments Office,
or follow the instructions below.
• Prepare a vessel containing ice and water and another one containing
hot water (around 50 ºC). Place insulation material around the vessels
to minimize temperature changes.
• Use a calibrated thermometer with a resolution of 0.1 ºC as a
reference thermometer. Connect the
HI7662
probe to the appropriate
socket for the pH temperature channel or the
HI76310
probe for the
EC temperature channel.
• With the instrument off, press and hold down the
CFM & SETUP
keys, then power on the instrument to calibrate the pH temperature
channel or
&RANGE
keys and then power on the instrument to
calibrate the EC temperature channel. The “
CAL
” tag will appear
and the secondary LCD will show “
0.0 ºC
“.
• Submerse the temperature probe (or EC probe) in the vessel with ice
and water as near as possible to the calibrated thermometer. Allow
a few seconds for the probe to stabilize.
• Use the
ARROW
keys to set the reading on the secondary LCD to that
of ice and water, measured by
the calibrated thermometer. When
the reading is stable and close to the selected calibration point, the
“
CFM
” tag will blink.
• Press
CFM
to confirm. The secondary LCD will show “
50.0 ºC
“.
TEMPERATURE CALIBRATION
(for technical personnel only)