User Guide

• Measure the sample at a different temperature "t°C" which should

be between 5°C to 10°C different from 25°C and note the

conductivity reading as "Ct".

• The temperature coefficient "ß" of the solution can be calculated

with the following formula:

(Ct - C25)

ß = 100 x ---------------------------

(t°C - 25) x C25

Some solutions, especially in horticulture, use 0.7 as the conversion

rate between conductivity and TDS instead of the common 0.5 CaCO

TDS factor.

The TDS factor of HI 9635 can be selected as 0.7 (F1) or 0.5 (F2).

• Press RANGE to enter TDS1 mode, that is Total Dissolved Solids

with a TDS factor of 0.7 (F0.70 is shown on the secondary

display).

• Press RANGE again to change to TDS2 mode, that is Total

Dissolved Solids with a TDS factor of 0.5 (F0.50 is shown on the

secondary display).

TDS FACTOR (HI 9635 TDS FACTOR (HI 9635

TDS FACTOR (HI 9635

onlyonly

only

))

)

ppm

TDS

1.95

RANGE

ppm

TDS

1.39

RANGE