MODEL | SECTION 10.0 |
| CALIBRATION – PH |
10.5 PROCEDURE — ENTERING A KNOWN SLOPE VALUE.
1.If the electrode slope is known from other measurements, it can be entered directly into the transmitter. 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) | 298 |
|
t°C + 273 |
Changing the slope overrides the slope determined from the previous buffer calibration.
2.Press MENU. The main menu appears. Choose Calibrate.
3.Choose pH.
4.Choose slope.
5.The screen at left appears briefly.
6.Change the slope to the desired value. Press ENTER.
7.The slope must be between 45 and 60 mV/pH. If the value entered is outside this range, the screen at left appears.
8.If the entry was accepted, the screen at left appears.
9.To return to the main display, press MENU then EXIT.
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