horiba LAQUA F-71G, Instruction Manual

Page: 61 / 102

Chapter 3 Basic Operation
3.3 Calibration
43
Electrode status
You can check the electrode status after calibration.
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Calibration with USA standard solution
It is possible to calibrate pH2, pH4, pH7, pH10, and
pH12 using USA standard solutions.
In this manual, an example of 2 points calibration with
the standard solutions of pH7 and pH4, which are used
generally, is explained.
The calibration order is arbitrary. In this example, the
procedures of calibration of pH7 are explained, and fol-
lowed by ones of pH4, but you can perform calibration in
an order as you like.
1.
Prepare the pH electrode. Wash the pH electrode
with pure water (deionized), and wipe it off by filter
paper or tissue paper.
Display Description
,ERR
No display
Good condition.
Electrode sensitivity: 93% to 100%
Blinks
Electrode sensitivity: 90% to 93%
・
Check that the standard solutions are
correct.
・
Wash the electrode.
"
●
Washing electrodes" P.65
Lights up
Electrode sensitivity: 85% to 90%
"
●
ERROR No.0005 Span calibration
error (pH)" P.69
ERROR
No.0004
It is the asymmetry potential error.
"
●
ERROR No.0004 Zero calibration
error" P.68
ERROR
No.0005
It is the sensitivity error.
"
●
ERROR No.0005 Span calibration
error (pH)" P.69