Hanna Instruments HI 931100 - Manual (Page 11)

21 20
TEMPERATURE CALIBRATION
(for Technical Personnel only)
INITIAL PREPARATION
Prepare a 0°C/32°F bath with ice and water and
another one at 50°C/122°F using hot water at a
known temperature. Place insulation material around
the containers to minimize temperature changes.
Use a Checktemp or another accurate thermometer
with a resolution of 0.1° as reference.
Note: A blinking "°C" indicates
that the temperature probe
is not connected.
PROCEDURE
• Connect the HI 7662 temperature probe to the
RCA socket on the top of the instrument.
• Turn the instrument off.
• To enter the temperature calibration mode, press
the CAL and ON/OFF keys simultaneously.
• Immerse the temperature probe
into the 0°C/32°F bath together
with the reference thermom-
eter.
• When the reading stabilizes,
press the CAL key. The
"0.0°C", "CAL" and "BUF"
symbols will be displayed. The
"
" symbol will blink for a
few seconds.
gm
°C
NaCl
0 °C
(32 °F)
°C
50 °C
(122 °F)
°C
°C
0°C
(32°F)
TEMPERATURE
The best working temperature is around 20-25°C
(68-77°F).
For greatest accuracy, it is recommended to cali-
brate the meter with standard solution at a tempera-
ture as close as possible to the temperature of the
sample (± 1°C/±2°F).
Na CONCENTRATION WITH HI 931100
It is always possible to determine the Na concentra-
tion by using the formula:
X
Na
= X
NaCl
• (23 / 58.4)
where
X
Na
= concentration of Na
and
X
NaCl
= concentration of NaCl
BUF CAL
°C