Velp Scientifica TB1 User manual

Instruction Manual
TB1
Portable Turbidimeter
VELP SCIENTIFICA
Constant Commitment to Knowledge Development
10000208/A8

Velp Scientifica –TB1 Manual
Preface
This manual functions in two ways: first as a step by step guide to help you
operate the waterproof TB1 turbidimeter; second, it serves as a handy
reference guide.
It contains basic instructions that you must follow during the operation,
care and maintenance of the instrument. The safety protection provided by
this equipment may be impaired if it is used in a manner not described in
this manual. It is recommended that all operators should read this manual
prior to working with this instrument.
The manufacturer does not acknowledge any responsibility for an
improper use of the equipment, not responding to directions for use.
Note: The manufacturer, engaged in a continuous improvement of his
products reserves the right to modify any of their characteristics without
notice.
Do not dispose of this equipment as urban waste

Velp Scientifica –TB1 Manual
TABLE OF CONTENTS
1 OVERVIEW 1
1.1 Unpacking TB1Meter and Accessories 1
1.2 Display 2
1.3 Keys and Functions 3
1.4 Battery Installation 4
2 TURBIDITY CALIBRATION 5
2.1 Indexing 5
2.2 Calibration Standards 5
2.3 Preparing the standard vials 6
2.4 Calibration Procedure 6
2.5 Restoring Factory Calibration 9
3 TURBIDITY MEASUREMENT 11
3.1 General Information 11
3.2 Turbidity Measurement Procedure 11
3.2.1 Preparation of Sample Vial 12
3.2.2 Measurement Procedure 13
3.3 Single-Shot or Continuous Measurement 14
4 TROUBLESHOOTING GUIDE 16
5 ROUTINE MAINTENANCE 17
5.1 Vials –Handling, Cleaning and Care 17
6 ACCESSORIES 18
7 SPECIFICATIONS 19
8 ADDENDUM 1: TURBIDITY 20
8.1 Definition 20
8.2 Why Is It Important? 20
8.3 Measurement Principle 20
8.4 Nephelometric Turbidity Units (NTU) 21
8.5 Indexing a Vial 21
9 ADDENDUM 2: GUIDE TO GOOD MEASUREMENT TECHNIQUE 22
9.1 Maintain sample vials in good condition 22
9.2 Match Sample Vials 22
9.3 Degassing 23
9.4 Timeliness of Sample 23
9.5 Other Important Sampling Techniques 23
9.6 Calibration 24
9.7 Dilution 24
10 WARRANTY 25

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1 OVERVIEW
Thank you for selecting the waterproof portable TB1 turbidimeter. The TB1
allows you to measure turbidity of an aqueous sample in the field. This
instrument operates on the nephelometric principle of turbidity
measurement and is designed to meet the criteria specified in ISO 7027
and DIN 27027 standards (see 8.3 Measurement Principle on page
20).
1.1 Unpacking TB1 Meter and Accessories
The table below indicates the items that you should find in your
turbidimeter shipment.
Item
Quantity
1. Field Portable TB1 Turbidimeter with 4 “AAA” batteries
1
2. Instruction Manual
1
3. Instrument Carrying Case
1
4. Light Shield Cap
1
5. Calibration Set (0.02, 20.0,100, 800 NTU Standards)
1
6. Empty Vials
3
7. Silicone Oil
1
8. Lint free cloth
1
Remove TB1 turbidimeter from the packing carton. Carefully inspect all
items to ensure that no visible damage has occurred during shipment. If
the items you received do not match your order, please contact your
nearest distributor immediately.
WARNING: Extra care should be taken when
unpacking, opening, and handling the calibration
standards and sample vials. Surface scratches or
finger smudges on the vial surface may cause
measurement errors. Handle these items by their
caps only.
Batteries provided with the meter package are to be installed prior to use.
See Section 0 - 1.4 Battery Installation on page 4.
Figure 1 depicts the meter. The three main components of the instrument
are the sample well, the display, and the keypad. The following sections
will describe the functionality of the display and the keypad. The proper
use of the instrument and the sample well will be discussed in later
sections.

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Figure 1: Parts of TB1 Turbidimeter
1.2 Display
All the LCD segments and annunciators that can appear on the display are
shown in Figure 2. The display is used for reporting the turbidity reading
and to provide guidance for the operation of the instrument. In addition,
the display has several other annunciators that are used to communicate
error messages and provide user guidance.
CAL 13 CAL 24 mg/l
NTU
ppm
%pH
TAvg
14-segment Liquid Crystal Display
Battery Indicator
Calibration
Standards
Units of
Measurement
Figure 2: Customized LCD when switched on
Sample Vial
Sample Well
Index Mark
Liquid Crystal Display
Keypad

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1.3 Keys and Functions
The keypad has five keys: ON/OFF, CAL, ▲, ▼, and READ/ENTER.
Keys
Functions
ON/OFF
-Powers on and shuts off the meter. With the auto switch-off
feature the meter automatically shuts off 20 minutes after last
key press.
CAL
-Initiates the calibration mode of the meter. When pressed, the
meter is set to accept the first calibration standard.
-It is also used to exit the calibration mode if the user does not
want to follow the complete calibration procedure.
READ /
ENTER
-When in measurement mode, the READ/ENTER key is used to
perform a measurement.
-Single-shot measurements: When the key is pressed and
released immediately (a quick key stroke of less than 0.3
seconds), the display will blink [-Rd-] for 10 times and then
display the measured value.
-Continuous measurements: If the READ/ENTER key is pressed
and held, the instrument will perform a continuous measurement
during which the display is updated every 2 seconds. This can
be used for indexing vials. (This function is not available in
calibration mode).
After the READ/ENTER key is released, the instrument will
automatically perform a single-shot measurement.
-When in calibration mode, the READ/ENTER key is used to
confirm the measurement for the calibration standards.
▲and▼
-Active only during calibration mode. These keys are used to
select the calibration point in an incremental/ decremental
manner.
NOTE: This meter is also fitted with an auto incrementing
feature, i.e. after the successful calibration of one point it auto
selects the next calibration point, or automatically exits the
calibration mode after the fourth calibration point.

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1.4 Battery Installation
Four AAA-sized batteries are included in your meter’s packaging:
1. Use a Philips screwdriver to remove the two screws holding the
battery cover. See Figure 3.
2. Remove the battery cover.
3. Insert the batteries. Follow the diagram inside the cover for correct
polarity.
4. Replace the battery cover onto its original position using the two
screws removed earlier.
5. The meter is now ready to operate.
Philips Screws
Battery cover
Four 'AAA'-sized batteries
Figure 3: Battery Installation
NOTE:
Dispose used batteries in accordance with your local
regulations.

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2 TURBIDITY CALIBRATION
The TB1 turbidimeter was calibrated and tested prior to leaving the factory.
Therefore, it is possible to use the instrument directly out of the box.
However, re-calibration of the instrument is recommended to help you
become familiar with the operation of the instrument and the calibration
procedures. In addition, re-calibration is recommended at least once every
month for optimum accuracy.
It is recommended that you perform a full calibration using all 4 standards
provided to ensure full-range accuracy. The meter kit now includes a set of
prepared SDVB primary standards in plastic bottles which are EPA-
approved for meter calibration. This keeps the stock solutions for the 0.02,
20.0, 100 and 800 NTU standards ready to use and offers improved
precision and shelf life. A set of 4 empty vials for the standards are
included in the meter kit. Before using the meter for the first time, verify the
meter calibration by reading back the value for the prepared primary
standard at the appropriate NTU value.
However, the TB1 turbidimeter provides flexibility for you to calibrate at
selected ranges suitable for your application.
In addition, the instrument comes with a light shield cap to shield off stray
light during calibration and measurements.
2.1 Indexing
Due to the high quality of the glass vials provided, indexing is not required.
You only need to align the mark on the vial with the mark on the meter.
However, in order to achieve a better accuracy of the measurement, you
can proceed with indexing of the vials. See Section 8.5 Indexing a
Vial on page 21 for more information.
2.2 Calibration Standards
We recommend that you use the following SDVB primary standard during
calibration to achieve the accuracy stated in this manual:
CAL 1: 800 NTU Calibration Standard
CAL 2: 100 NTU Calibration Standard
CAL 3: 20.0 NTU Calibration Standard
CAL 4: 0.02 NTU Calibration Standard
It is well known that diluted Formazin is unstable. If you choose to use
Formazin to calibrate the instrument, ensure that you are using a fresh
stock suspension of Formazin to achieve the accuracy quoted for the

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instrument. The SDVB Calibration standards offered are more stable than
Formazin and have a shelf life until the expiration date on the plastic
bottle. These are primary standards that meet the regulatory requirements
for reporting for ISO and US EPA.
2.3 Preparing the standard vials
Each standard vial should be used with the same standard value (0.02,
20.0, 100, or 800 NTU) for the greatest accuracy. Follow the steps below
at each change of solution.
1. Ensure there are no scratches or marks on the glass vial. If there are
marks that could affect the turbidity measurement, select another vial.
2. Slowly and gently invert the calibration stand plastic bottle five times but
do not shake the bottle as air bubbles can affect the reading.
3. Rinse a clean vial with 3-4 ml of the calibration standard that will be
used in this vial. Invert the capped vial 5 times. Uncap and dispose of the
rinsate.
4. Repeat the rinsing steps and dispose of the rinsate.
5. Fill the vial with the primary standard solution to the fill line and cap the
vial.
6. Clean the exterior of the vial using a lint-free cloth to remove all traces
of liquid, dirt or fingerprints. Remove stubborn smudges with alcohol or a
non-abrasive glass cleaner, and silicone oil can be used to fill small
external scratches on the vial.
7. Repeat Steps 1-6 to prepare the other three standard solutions.
These standard vials can be used to check the meter calibration by
reading back the standard value daily and also be used for calibration
when needed. When the standard reading drifts more than 10% of the
standard’s NTU value, the solution should be replaced with another aliquot
from the plastic bottle following the Preparing the Standard Vials steps.

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2.4 Calibration Procedure
When calibration is required fresh standards from the plastic bottle are
recommended for the greatest accuracy. Follow the calibration sequence
from highest, 800 NTU, down to lowest standard, 0.02 NTU. See Section
2.3 “Preparing the standard vials” prior to starting the calibration.
1. Place the TB1 turbidimeter on a flat and level surface.
2. Select the calibration function of the instrument by pressing the CAL
button once. The [CAL] annunciator will blink momentarily and the
meter will prompt for the first calibration standard CAL 1 standard (800
NTU).
3. Insert the CAL 1 standard (800 NTU) into the sample well, aligning the
mark on the vial with the mark on the meter. See Figure 10
4. Press down until the vial snaps fully into the instrument.
5. Cover the vial using the light shield cover.
6. Press READ/ENTER key.
7. The [CAL 1 800 NTU] annunciator will blink for about 12 seconds.
When the instrument has completed calibration for this point, it prompts
you to insert the next calibration standard into the sample well [CAL 2
(100 NTU).
8. Repeat the calibration sequence for each calibration standard.
9. After you successfully calibrate the CAL 4 standard (0.02 NTU), the
display will show [STbY].
10.The meter is now ready to perform next measurement.
Figure 4 shows the complete calibration sequence.
NOTES:
1. If you wish to exit the calibration mode you may
do so at the end of any step by pressing the CAL
key. The meter will accept only the values
calibrated prior to exiting.
2. You can skip a calibration point by pressing ▲ or
▼ keys and move on to the next calibration point.
3. After a successful calibration of one point, it will
auto select the next calibration point. It will
automatically exit calibration mode after the fourth
calibration point.
4. If an error occurs during calibration, the display
will present an error message. The meter will
abort calibration and return to the measurement
mode without saving the last calibration value.
5. For a list of error messages, refer to Section 4:
Troubleshooting Guide.