Temperature compensation: When measuring pH using a
pH electrode the temperature error from the electrode varies
based on the Nernst Equation as 0.03pH/10C/unit of pH
away from pH7. The error due to temperature is a function
of both temperature and the pH being measured.
Temperature compensation can be achieved manually or
automatically. Manual temperature compensation is usually
achieved by entering the temperature of the fluid being
measured into the instruments menu and then the instru-
ment will display a "Temperature Compensated" pH reading.
This means that the temperature is corrected to the value
expected at 25 Deg C. Automatic temperature compensa-
tion requires input from a temperature sensor and constant-
ly sends a compensated pH signal to the display. Automatic
temperature compensation is useful for measuring pH in
systems with wide variations in temperature.
pH Electrode
basics
pH Electrodes
9
www.milwaukeeinst.com
Model
MA905B/3 MA913B/3 MA923B/3
Measuring Range 0 to 13 pH 0 to 13 pH ±1999 mV
Temperature Range -5 to 95°C 0 to 60°C (32 to 140°F) 0 to 80°C (32 to 176°F)
Shaft Material Epoxy Epoxy
Reference Electrolyte polymer gel gel
Reference Junction double, Teflon ceramic, single cloth
Reference Type single, Ag/AgCl single, Ag/AgCl
Shape of membrane spheric spheric pH: conic / ORP: Platinum sensor
Max pressure 6 bar 2 bar 3 bar
Connector Type 3/4” NPT - BNC BNC DIN
Cable length 3 m coaxial, 3 m 7-pole, 1 m
Shaft length 120 mm 120 mm 120 mm
Diameter 22 mm 12 mm 14 mm
Application industrial applications water, waste water water, waste water
12 mm
120 mm
12 mm
120 mm
22 mm
120 mm
M
A
9
2
3
B
/3 =3 m
M
A
9
1
3
B
/3 =3 m
M
A
9
0
5
B
/3 =3 m
DIN Connector
BNC Connector
