YOKOGAWA PH72-21-E-AA, User Manual

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IM 12B03D02-01E
6-1
6. Maintenance
6. Maintenance
6.1 For Optimum Meter Performance
The Model PH72 Personal pH/ORP Meter is simple to operate, but is a precision
instrument. To ensure accurate results from the meter, the following precautions should
be observed.
Flow Diagram
Measurement
Maintenance Calibration
Storage
F060101.EPS
Table 6.1 Precautions in Each Step
Calibration
Measurement
Maintenance
Storage
T0601.EPS
Calibration using standard solutions:
• 1- or 2-point calibration. 2-point calibration is recommended for
accurate pH measurement.
• Always use certified standard solutions (pH 2, 4, 7, 9, 10, or 12).
Sample solution requirements:
• pH range: 0 to 14 pH
• Temperature: 0 to 80
8
C (0 to 100
8
C when using needle type or test
tube size pH sensor)
• After measurement, rinse off remaining sample solution from the
electrode thoroughly.
• Avoid a place with high temperature and humidity.
• Keep the wetting cap (moisten the cotton wad in the cap with a few
drops of water) attached to prevent the glass electrode and liquid
junction from drying out.