1. If the electrode slope is known from other measurements, it can be entered directly into the controller. The
slope must be entered as the slope at 25°C. To calculate the slope at 25°C from the slope at temperature t°C,
use the equation:
slope at 25°C = (slope at t°C)
Changing the slope overrides the slope determined from the previous buffer calibration.

12.5 pH SLOPE ADJUSTMENT

MODEL 54eA SECTION 12.0
CALIBRATION - pH
Adjust temperature
Calibrate pH
Output trim
Exit Enter
Buffer calibration
Standardize pH
pH slope
Exit Enter
2. From the main display, press any key to obtain the main menu. With
the cursor on "Calibrate" press Enter (F4).
NOTE
If Hold was enabled in Section 5.6, the hold screen will appear.
To activate hold, refer to Section 5.6, step 11.
3. Press the key three times to move the cursor to "Calibrate pH".
Press Enter (F4).
4. Press the key twice to move the cursor to “pH slope.” Press Enter
(F4).
5. Press Edit (F4). Use the arrow keys to change the slope to the
desired value. The slope msut be between 45 and 60 mV/pH. Press
Save (F4).
6. Press Exit (F1) four times to return to the main display.
NOTE
If Hold was activated during calibration, “Hold Mode Activated”
will continue to flash in the main display. Return the sensor to
normal and deactivate Hold. Refer to Section 5.6, step 11.
pH slope: 60.00 mV/pH
Exit Edit
298
t°C + 273
NOTE
During calibration, ERROR and WARNING messages may appear. If an ERROR message appears, press
Exit (F1) to leave and return to the previous screen. If a WARNING message appears, press Cont (F3) to
continue the calibration or press Abort (F1) to leave. Continuing the calibration after a warning message
appears may cause substantial errors in the subsequent measurement. Refer to Section 15.9 for assis-
tance.
77