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Turbimeter Plus
Compact Turbimeter
Average Mode
To index a cuvette, insert the sample cuvette
with the orientation mark facing forward.
Choose 'Reading' mode, select 'Average'
Systematically rotate the sample cuvette 45°
and press 'OK'.
at a time and record the position of the lowest
Select the number of readings required
value. This is the optimal cuvette alignment for
for the averaging function:
low turbidity measurement.
Short
3 consecutive readings
Total Suspended Solids
Medium 6 consecutive readings
This mode will only be active if a site calibration has
Long
12 consecutive readings
been stored within the Turbimeter. Once a calibration
Insert the sample with the orientation mark facing
has been created (via the 'Calibration' menu) the site
forward or aligned with the optimal indexed
ID can be used to recall the site specific relationship
point and press 'Read'.
between turbidity and suspended solids.
Choose 'Reading' mode, select 'Total Suspended
The instrument will beep at the start and end
Solids' and press 'OK'. Highlight the Site ID for
of measurement cycle.
the Site/Sample under investigation using the
Result is displayed on the screen and stored
Up/Down arrows. The calibration data will be
in the log with time, date, Operator ID and
recalled automatically.
Sample ID.
Insert the sample with the orientation mark facing
forward and press 'Read'. A beep will occur at
Continuous-Capture Mode
the start and end of each measurement cycle.
Insert the sample with the orientation mark
Result is displayed on the screen in mg/l and
facing forward or aligned with the optimal
stored in the log with time, date, Operator ID
indexed point.
and Sample ID.
Choose 'Reading' mode, select 'Continuous-
Capture' and press 'Read'.
4.7 Calibration Menu
A beep will occur at the start and end of each
The Compact Turbimeter is delivered with a stored
measurement cycle.
calibration carried out on primary Formazin
standards and validated as part of the production
To store data in the log, press 'Capture'
process. For field use, a set of calibration
(repeat as required).
standards are provided as part of the kit.
To cease measurement, press 'Stop' at any time.
Recalibration is only required if the standards
To index a cuvette, insert the sample cuvette
provided show an unacceptable level of variation
with the orientation mark facing forward.
from the stated values on read-back.
Systematically rotate the sample cuvette 45° at a
Two different methods of calibration are
time and markthe position of the lowest value on
available for the Turbimeter.
the glass. This is the optimal cuvette alignment
The calibration methods are:
for low turbidity measurement.
SDVB
Total Suspended Solids
The use of SDVB for field calibration of turbidity
This mode will only be active if a site calibration
meters is preferable due to the improved stability and
has been stored within the Turbimeter Plus.
handling compared to Formazin. When calibrating
Once a calibration has been created (via the
turbidity instruments SDVB standards are assigned
'Calibration' menu) the Sample ID can be used
to a specific model and cannot be transferred.
to recall the site specific relationship between
Using SDVB standards from another manufacturer
turbidity and Total Suspended Solids.
may differ greatly when applied to the
Choose 'Reading' mode, select 'Total Suspended
Turbimeter. This is normal behaviour and
Solids' and press 'OK'.
should not cause concern.
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Highlight the Sample ID for the Site/Sample
Formazin
under investigation using the Up/Down arrows.
Freshly prepared standards can also be used for
Only Sample IDs with Total Suspended Solids
calibration where available.
calibrations will be shown. The calibration data
Formazin is used as the primary calibration material
will be recalled automatically.
for the Turbimeter and can also be used to align
Insert the sample with the orientation mark facing
the calibration of different instruments when
forward or aligned with the optimal indexed
discrepancies occur. Preparation of Formazin
mark and press 'Read'.
standards from 4000NTU stock solution is required
to be within the stated limits detailed below.
A beep will occur at the start and end of each
measurement cycle.
Total Suspended Solids
When using the Turbimeter in Total Suspended Solids
Result is displayed on the screen in mg/l and
Reading mode, a calibration is required to set the
stored in the log with time, date, Operator ID
relationship between the measured turbidity values
and Sample ID.
and the 'true' suspended solids value, determined by
gravimetric methods. This calibration can either be
4.7 Calibration / Check Menu
an assigned series of values from the results log
or a simple algorithm with factors provided by the
The Turbimeter Plus is delivered with a stored
user. This relationship is typically a straight line and
calibration carried out on primary Formazin
hence the factors consist of a slope and intercept.
standards and validated as part of the production
The Compact Turbimeter has two methods of
process. For field use, a set of calibration
generating the data for relating the measurement
standards are provided.
of turbidity to total suspended solids (TSS):
Recalibration is only required if the standards
1 Correlation - Using the stored turbidity data
provided show an unacceptable level of variation
from the instrument log and relating it to
from the stated values on read-back or using the
manually entered Total Suspended Solids data
Check Standard Read routine.
derived from elsewhere. The minimum number
Two different methods of calibration are available
of correlation points required is one, as the zero
for the Turbimeter Plus.
point can be used as a second point. A maximum
number of 50 data points can be used.
SDVB
2 Factor - Using data manipulated externally,
The use of SDVB for field calibration of turbidity
a slope and intercept for the straight line
meters is preferable due to the improved
relationship can be entered directly. Slope
stability and handling compared to Formazin.
factors range from 0.1 - 50.0 and intercepts
When calibrating turbidity instruments SDVB
can be set from -50.0 - +50.0
standards are assigned to a specific model and
cannot be transferred or used with other models
Calibrating the Compact Turbimeter
or manufacturers.
SDVB
Select Calibration and press 'OK'.
Formazin
Choose 'SDVB' and press 'OK'.
Freshly prepared standards can also be used for
Select the lowest (0.05 - 0.15) NTU standard and
calibration where available. Formazin is used as
insert into the sample chamber with the orientation
the primary calibration material for the Turbimeter
mark facing forward.
Plus and can also be used to align the calibration
Use the Up/Down buttons to adjust the value on
of different instruments when small discrepancies
screen to that on the standard and press 'Read'.
occur. Preparation of Formazin standards from
4000 NTU stock solution is required to be within
Repeat the process for the 20NTU, 100NTU
the stated limits detailed below.
and 800NTU standards.
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