Xylem IQ SensorNet ViSolid 700 IQ (SW) User Manual

Page 36

Measuring

ViSolid

700 IQ (SW)

4 - 8

ba76040e02

07/2013

Note
A measurement of the total suspended solids will deliver ever more
accurate measurement results the closer the composition of the
measuring medium corresponds to the status at the time of the
calibration. If there is a fundamental change of the characteristics of the
sample, a new calibration may be necessary.

Procedure of the

calibration

Note
At least one value pair and a maximum of eight value pairs can be
entered for a valid calibration. Keeping to the descending order of
values is very important. Not keeping to the order will result in a
calibration error.

Note
Samples of different concentrations of total suspended solids can be
obtained from the sample taken by:

 diluting it with water
 depositing the total suspended solids and decanting off the

remaining water

Before measuring the samples, make sure that the total suspended
solids are actually in suspension.

Bring the sensor into the measuring position.

In the setting table of the TSS sensor, select the
mg/l TSS measuring mode and the AutoRange measuring
range (see section 3.5.3).

Switch to the measured value display with .

When the measured value is stable, read the SiO2 value
(marked with "#"), convert it into the unit (mg/l) if necessary,
and note it down.

Take a sample as close to the same time as the SiO2
measurement as possible and as close to the sensor as
possible.

Determine the level of total suspended solids of the sample
according to a reference procedure (e.g. gravimetric according
to DIN 38414) and note it down together with the measured
value of SiO2 as the TSS/SiO2 value pair in mg/l.

For a multi-point calibration:
Repeat the determination of the value pair for various
concentrations of the sample.