ABB 4630, Руководство по эксплуатации

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16
pH CALIBRATION
– – – – –
0 0 0 0 0
Cal . User Code
Buffering 1 Pt
– – – – –
Immerse Buffer
Calibrating Buf
– – – – –
% Slope Value
SECURITY CODE
0 0 0 0 0
pH Check Value
Auto
Man
or
Calibration Pass
Slow Response
1 7 5
.
l 0 0 0
.
7 0 0
.
4 0
.
…6 OPERATION
6.2.2 Single Point pH Calibration
A single point calibration may be carried out in preference to a two point calibration provided a two point calibration has been
carried out since installing the instrument. This procedure assumes an electrode pair with perfect Nernstian response, i.e.
59.16mV per pH change at 25
°
C. Refer to Table 6.1 on Page 13 for an overview of the calibration procedure.
✶
Note. Pressing the key at any point during the calibration sequence prior to
the pH Check Value parameter aborts calibration and returns the display to the top
of the
Operating Page
.
Advance to next parameter.
Calibration Access
Enter the required calibration code number, between 00000 and 19999. If an incorrect
value is entered, access to pH calibration is prevented and the display returns to the top
of the
pH Calibration Page
.
Advance to next parameter.
Buffering Calibration Type
Select single point buffering (
1 Pt ).
Advance to next parameter.
Buffer Calibration
Immerse the electrode in the buffer solution. Set the upper display line to the
temperature-corrected pH value of the buffer solution – refer to the datasheet
accompanying the solution.
Advance to initiate calibration. A flashing dot indicates that calibration is in progress.
The upper display line shows the sensor e.m.f.
• When a stable e.m.f. is detected, the instrument automatically advances to the next
parameter and the calibration message appropriate to the result of the calibration is
displayed.
• If a stable e.m.f. is not detected, the calibration message Slow Response is
displayed.
Calibration Message
Refer to Table 6.3 on page 20 for calibration message clarification.
Advance to next parameter.
Slope Value
The slope value remains fixed from the last 2-point calibration.
Advance to next parameter.
pH Check Value:
is displayed as an additional indication of electrode system condition; 7pH being the
optimum value for glass electrodes and 0pH for Antimony electrodes.
Advance to
Access to Secure Parameters
.