Instruction manual

Instruction Manual PC 510

8.8.4 P7.4: Setting the TDS factor

The concentration of salts dissolved in solution increases the conductivity of that solution. This

relationship varies from salt to salt and is roughly linear over a given range for a given salt. The TDS

conversion factor is the number used by the meter to convert from conductivity to TDS.

To determine the conductivity to TDS conversion factor for your

solution:

Addendum 1 and 2 on this sheet describes the conversion factors and

how to calculate the TDS conversion factor for other solutions.

You can set the TDS conversion factor between 0.4 and 1.0; meter

default is 0.5. When the factor is set to 1.0, conductivity = TDS.

From measurement mode

1. Press SETUP key to enter Setup mode.

2. Press the  or  key to scroll through sub-groups until you view

parameter P7.0.

3. Press the ENTER key four times to select parameter P7.4. The

upper display shows “tdS” and the lower display shows “P7.4”.

4. Press the ENTER key again. The upper display shows a value and

the lower display shows “tdS”.

5. Calculate the TDS factor of your solution. See Addendum 2 on this

sheet for information on how to calculate the TDS factor.

6. Press the  or  key to select your calculated TDS conversion

factor.

7. Press the ENTER key to confirm selection and to return to the sub-

group menu. Press the CAL/MEAS key to return to the

measurement mode.

Figure 38: Change of TDS factor

ppt

ppm

SETUP

p 7.4

ppt

ppm

SETUP

0.50

ppt

ppm

SETUP

0.75