Thermo Fisher Scientific CyberScan pH 5000 - Manual (Page 61)

Instruction Manual CyberScan pH5500/ 5000
The Isopotential point is the millivolts reading for an electrode at
which temperature has no effect on the measurement. pH electrodes
are constructed so that the isopotential point is theoretically zero
millivolts. This is very close to a pH of 7. Most pH electrodes do not
achieve this value precisely. However, they are close enough so that
it is not usually necessary to use an isopotential point other than zero.
The true isopotential point of any given electrode must be determined
experimentally. (See appendix: Determining Isopotential Points
Experimentally, pg 124)
To Set Isopotential Point
1. Access the Set Isopotential Point screen from the pH (Ion) Setup
screen. The current isopotential point is displayed on the screen.
2. Touch clear to remove the current mV Value.
3. Use the numeric keypad to enter the desired mV setting for the
new isopotential point.
4. Touch enter to accept this value and return to the pH (Ion) Setup
screen.
OR
Touch exit to return to the pH Setup screen, without making any
changes.
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