Thermo Fisher Scientific CyberScan pH 1000/pH 2500 - Manual (Page 13)

Instruction Manual pH 1000/ 2500
8
HINT: For best results, perform
at least a 2-Point Calibration
using buffers that bracket the
expected range of
measurement. If a 1 Point
Calibration is to be used, it is
highly recommended that
measurement be performed
only at points close to the
calibration value.
The primary display of the LCD shows
the measured pH value; the
secondary display shows the value of
the standard solution (pH 1.68, 4.01,
7.00, 10.01, 12.45). To select other
buffer values, use arrow keys.
6 CALIBRATION
6.1
pH Calibration (With ATC)
The pH 1000/ 2500 bench meter is capable of multi-point
calibration up to 5 points for enhanced full range accuracy
using standard pH buffer options at pH 1.68, 4.01, 7.00,
10.01 and 12.45. In addition, these meters allow added
flexibility for you to calibrate using other non-standard
calibration buffers (via the CAL EDIT feature).
6.1.1
1 Point pH Calibration
1. Make sure the meter is ON and if necessary, press the MODE
key to select pH mode. The pH indicator appears in the upper
right hand corner of the display.
2. Rinse the electrode thoroughly with deionised water or a rinse
solution. If using the ATC function with a separate temperature
probe, rinse the temperature probe as well. DO NOT wipe both
probes dry as it will cause a build-up of static and create
instability in calibration and measurement.
3. Select the pH buffer and pour some into a clean container.
Immerse both probes into the selected buffer and press CAL
key, a [CAL] annunciator appears. The primary display shows
the measured pH reading while the secondary display indicates
the pH buffer value for calibration.
4. Select the correct buffer value on the meter. If the buffer used
is a standard value, use OPTION 1. Otherwise use OPTION 2
to calibrate the meter to the required value.
6.1.2 Option 1 - Standard Buffers
Select desired pH buffer standard using S or T key to scroll
to the correct buffer value as indicated in the secondary
display to that of the prepared buffer solution.
If the selected buffer is not within the accepted window (see
below) from the measured pH value, the electrode and
buffer icons flash and [ERR] annunciator appears next to the
secondary display.
Window of Accepted Values:
pH 1.68
±1.00
pH 10.01
±1.00
pH 4.01
±1.00
pH 12.45
±1.00
pH 7.00
±1.50
1. When reading stabilizes, a [READY] annunciator is displayed
on left hand side of the LCD. Note the READY annunciator will
be displayed after you have activated this function prior to
measurement or calibration. For details refer to Section 7.1.
2. Press YES to confirm calibration or NO to cancel and re-enter.
Upon confirmation, the CON indicator flashes at the top right
hand side of the LCD to indicate that the instrument is now
calibrated to the selected buffer. The secondary display
automatically scrolls to the next pH buffer option.
3. You have performed one-point calibration successfully using
standard buffer option after pressing YES key. To resume to
measurement mode, press CAL/MEAS key while you are in
the calibration mode.
Note: The LCD will display
the actual pH value of
the buffer at the point of
calibration. For example,
a pH 10.01 (@ 25
o C)
buffer when calibrated at
20
o C will actually have a
value of pH 10.06.
Therefore, the meter will
display this value of 10.06.