Myron L 3P - Manual (Page 7)

6. Press to accept the new value. The pH Zero Calibration is
now complete. You may continue with pH Gain Calibration or exit
by pressing either measurement key.
b. pH Gain Calibration
Important : Always calibrate or verify your Ultrameter with a pH 7 buffer
solution before adjusting the gain with acid or base buffers, i.e. 4 and/or
10, etc. Either acid or base solution can be used for the 2nd point “Gain”
calibration and then the opposite for the 3rd point. The display will verify
that a buffer is in the sensor well by displaying either “Acd” or “bAS”.
1. The pH calibration mode is initiated by either completion of the
pH Zero Calibration, or verifying 7 buffer and pressing the
twice while in pH measurement mode.
2. At this point the “ CAL ”, “ BUFFER ” and “ Acd ” or “ b A S ”
annunciators will be lit (see Figures 2 and 3).
N O T E : If the “Acd ” and “b A S ” indicators are blinking, the unit is
sensor well.
3. Rinse sensor well 3 times with acid or base buffer solution.
4. Refill sensor well again with same buffer solution.
5. Press or until display agrees with buffer value.
6. Press to accept 2nd point of calibration. Now the display
shows the next type of buffer to be used.
11
CAL
MCLR
Figure 3 Figure 2
M S
CAL
MCLR
MR
indicating an error and needs either a acid or base solution present in the
pH
BUFFER
CAL
pH
BUFFER
CAL
C. Calibration Procedures
1. pH Calibration
Important : Always “zero” your Ultrameter with a pH 7 buffer solution
before adjusting the gain with acid or base buffers, i.e., 4 and/or 10, etc.
a. pH Zero Calibration
1. Rinse sensor well 3 times with 7 buffer solution.
2. Refill sensor well with 7 buffer solution.
3. Press to verify the pH
calibration. If the display
reads 7.0, skip the pH Zero
Calibration and proceed to
section b. pH Gain Calibration.
4. Press to enter calibration mode. The “ CAL ”, “ BUFFER ”
and “ 7 ” annunciators will appear (see Figure 1). Displayed value
will be the uncalibrated sensor.
N O T E S : If a wrong buffer is added (outside of 6-8 pH),“7 ” and
BUFFER ” will flash, and the Ultrameter will not adjust.
The uncalibrated pH value displayed in step 4 will assist in determining
the accuracy of the pH sensor. If the pH reading is above 8 with pH 7
buffer solution, the sensor well needs additional rinsing or the pH sensor
is defective and needs to be replaced.
5. Press or until the display reads 7.0.
N O T E : Attempted calibration of >1 pH point from factory calibration will
cause “FAC ” to appear. This indicates the need for sensor replacement
(ref. Troubleshooting Chart, pg. 18) or fresh buffer solution. The “FAC”
internal electronic calibration is not intended to replace calibration with pH
buffers. It assumes an ideal pH sensor. Each “FAC” indicates a factory
setting for that calibration step (i.e., 7, acid, base).
You can press to accept the preset factory value, or you can
reduce your variation from factory setting by pressing or .
10
pH
CAL
MCLR
Figure 1
M S
MR
M S
MR
CAL
MCLR
pH
BUFFER
CAL
CAL
MCLR