11
•
Rinse the temperature probe of a
ChecktempC
(or
ChecktempF
) or another
accurate thermometer, and place it close to the pH electrode.
•
Use the UP and DOWN arrow keys to manually adjust the temperature to
match the reference thermometer.
•
Follow the pH calibration procedure explained in the previous pages.
The temperature has an effect on pH. The calibration buffer solutions are affected
by temperature changes to a lesser degree than normal solutions. During
calibration the instrument will automatically calibrate to the pH value correspond-
ing to the measured or set temperature.
During calibration the instrument will display the pH buffer value at 25°C.
p
pp
pp H BUFFER TEMPERATURE DEPENDENCE
H B U F F E R T E M P E R A T U R E D E P E N D E N C E
H B U F F E R T E M P E R A T U R E D E P E N D E N C E
H B U F F E R T E M P E R A T U R E D E P E N D E N C E
H B U F F E R T E M P E R A T U R E D E P E N D E N C E
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
32
41
50
59
68
77
86
95
104
113
122
131
140
149
158
167
176
185
194
203
4.01
4.00
4.00
4.00
4.00
4.01
4.02
4.03
4.04
4.05
4.06
4.07
4.09
4.11
4.12
4.14
4.16
4.17
4.19
4.20
7.13
7.10
7.07
7.04
7.03
7.01
7.00
6.99
6.98
6.98
6.98
6.98
6.98
6.99
6.99
7.00
7.01
7.02
7.03
7.04
10.32
10.24
10.18
10.12
10.06
10.01
9.96
9.92
9.88
9.85
9.82
9.79
9.77
9.76
9.75
9.74
9.73
9.74
9.75
9.76
TEMP pH VALUES
°C °F 4.01 7.01 10.01
18
For refillable electrodes, if the refill solution (electrolyte) is more than 2.5 cm (1")
below the fill hole, add the appropriate electrolyte solution.
MEASUREMENT
Rinse the electrode tip with distilled water, immerse it (4 cm / 1½") in the
sample and stir gently for a few seconds.
For a faster response and to avoid cross contamination of the samples, rinse the
electrode tip with the solution to be tested, before taking any measurements.
STORAGE PROCEDURE
To minimize clogging and ensure a quick response time, the glass bulb and the
junction should always be kept moist.
When not in use, store it with a few drops of
HI 70300
storage solution in the
protective cap.
NEVER STORE THE ELECTRODE IN DISTILLED OR DEIONIZED WATER.
PERIODIC MAINTENANCE
Inspect electrode and cable. The cable used for the connection to the meter must
be intact and there must be no points of broken insulation on the cable or
cracks on the electrode stem or bulb. If any scratches or cracks are present,
replace the electrode. Rinse off any salt deposits with water.
Connectors must be perfectly clean and dry.
For refillable electrodes:
For refillable electrodes:
For refillable electrodes:
For refillable electrodes:
For refillable electrodes:
Refill the electrode with fresh electrolyte (see the electrode’s specifications to select
the correct refilling solution). Allow the electrode to stand upright for 1 hour.
Follow the Storage Procedure above.
CLEANING PROCEDURE
•
General
Soak in
HI 7061
general cleaning solution for approxi-
mately 30 minutes.
•
Protein
Soak in
HI 7073
protein cleaning solution for 15 min.
•
Inorganic
Soak in
HI 7074
inorganic cleaning solution for 15
minutes.
•
Oil/grease
Rinse with
HI 7077
Oil & Fat cleaning solution for 1
minute.
IMPORTANT:
After performing any of the cleaning procedures, rinse the
electrode thoroughly with distilled water and soak it in
HI 70300
storage
solution for at least 1 hour before taking measurements.
