Hach-Lange POLYMETRON 83xx User Manual - Manual (Page 11)

2 E LECTRODES C ONDUCTIVITY P ROBE - I NSTRUCTION M ANUAL
621=183=000 Issue B 09/2010 Page 7
C
Tref
= C
T
[1 + " (T - T
ref
)]
-1
C
Tref
: Conductivity compensated to the
reference temperature
C
T
: Conductivity measured at T
T
ref
: Reference temperature
(generally 25°C)
" :
Temperature coefficient of the solution
(% / °C)
• For the sufficiently concentrated solutions
(natural waters, process…) the coefficient
is constant and is situated around 2 %.
• For slightly concentrated solutions, the
concentration of H+ protons and hydroxyl
OH- ions (stemming from the weak
dissociation of the water [H+] = [OH-] =
10
-7
mol/l to 25°C) can no longer be
neglected in the presence of the product,
this therefore leads to a non-linear
variation (compensation curve NaCI and
HCI).