Calibration Menu Flow Chart; Ph Sensor Calibration; Double Point Calibration - ABB AW400 Series Instruction Manual

6.1.2

Calibration Menu Flow Chart

Operation display
Process
Password
XXXXX
1,2,3.....
Menu
Channel 1
*S.P.C.
Channel 1
Calibration P1
Channel 1
Calibration P2
To Exit
menu
* Only when pH parameter is selected
6.1.3

pH Sensor Calibration

The calibration procedure is necessary to standardise the sensor sensitivity.
The double point calibration gives the maximum accuracy because it allows to set both the slope and the
offset of the curve giving displayed pH value as a function of the mV from the probe (sensitivity), pH = f (mV).
The first point can be calibrated by 7 pH buffer solution (0mV) and the second point can be calibrated by 4pH
buffer solution.
6.1.3.1

Double point calibration

The calibration procedure involves a series of operation on the pH probe and the transmitter. The following
description explains indicates step by step the calibration procedure.
To operate the calibration the following material is necessary:
- two plastic or glass beakers
- standard buffer solution, pH 7 and pH 4 or other, (see paragraph 6.1.3)
- de-mineralised water
- a thermometer
Calibration
Channel 2
*S.P.C.
Selects
Channel 2
P1 value
Calibration P1
Moves
to next
choice
Channel 2
Selects
Calibration P2
P2 value
Only when Channel 2
pc board is installed
Chann.Definition
Channel 3
Calibration P1.
Channel 3
Calibration P2
Only when Channel 3
pc board is installed
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