Apera TN400 User manual

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TN400 Portable Turbidity Meter
Instruction Manual
APERA INSTRUMENTS LLC
www.aperainst.com

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Table of Contents
1Overview...................................................................................................... - 3 -
2Technical Specifications ................................................................................ - 4 -
2.1 Technical Parameters.................................................................................................- 4 -
2.2 Others.......................................................................................................................- 4 -
3Instrument Description................................................................................. - 5 -
3.1 Instrument Overview ................................................................................................- 5 -
3.2 Meter and Accessories ..............................................................................................- 6 -
3.3 Display......................................................................................................................- 7 -
3.4 Keypad......................................................................................................................- 7 -
3.5 Battery Installation....................................................................................................- 8 -
4Meter Calibration ......................................................................................... - 8 -
4.1 Calibration Standards ................................................................................................- 9 -
4.2 Calibration Procedure................................................................................................- 9 -
4.3 Calibration Notes ....................................................................................................- 10 -
5Turbidity Measurement.............................................................................. - 11 -
5.1 Sample Vial Handling...............................................................................................- 11 -
5.2 Measurement Preparation ...................................................................................... - 11 -
5.3 For Single Measurement..........................................................................................- 12 -
5.4 For Continuous Measurement .................................................................................- 12 -
5.5 Measurement Notes................................................................................................- 12 -
6Warranty.................................................................................................... - 15 -

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1 OVERVIEW
Thank you for selecting our portable TN400 turbidity meter.
This meter is an outstanding combination of the most advanced electronic
technology and software design, and is the most cost-effective portable
turbidity meter. This meter operates on the nephelometric principle of turbidity
measurement and is designed to meet the criteria specified in ISO7027 and
DIN 27027 standards. TN400 allows you to measure the turbidity of an
aqueous sample both in laboratory and in the field.
With built-in microprocessor chips, elegant design, easy to use, the meter has
the following remarkable characteristics:
Smart functions, such as automatic calibration, operating instructions,
automatic power-off, low voltage display and etc.
Large TFT color screen, with blue background in measuring mode, green
background in calibration mode, and text and graphics in operational
directive.
With advanced digital processing technology, the accuracy of the meter is
greatly improved.
The structure design meets the requirements of IP67 level of protection and
is suitable
for use in field and on-site.
Contained in customized portable case, calibration standards, sample vials
and other
necessary accessories are more convenient to use and carry.

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2 TECHNICAL SPECIFICATIONS
2.1 Technical Parameters
Measuring Method
ISO 7027 compliant nephelometric method（90°）
Measuring Range
0 to 1000 NTU, automatic range selection:
0.01 to 19.99 NTU
20.0 to 99.9 NTU
100 to 1000 NTU
Resolution
0.01 / 0.1 / 1 NTU
Reading Error
≤ ±2 % of reading±stray light
Repeatability
≤ ±1% of reading or 0.02 NTU, whichever is greater
Calibration
Standards
0.02 NTU, 20.0 NTU, 100 NTU, 800 NTU(Polymer)
Light Source
Infrared light emitting diode（850nm wavelength）
Detector
Silicon photovoltaic
Display
TFT Color screen
Sample Vials
Φ25×60 mm, high borosilicate glass with screw cap
Sample Volume
18 ml
Operating Temp.
Range
0 to 50°(32˚F to 122˚F)
2.2 Others
Power Supply
4× AA Alkaline Batteries
IP Rating
IP67
Dimension/Weight
Meter：(90×203×80)mm / 385 g
Portable Case：(310×295×110)mm / 1.5 kg
Quality and Safety
Certificate
ISO9001:2008 & CE

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3 INSTRUMENT DESCRIPTION
3.1 Instrument Overview
①
Housing
⑥
Sampling well
②
Flip cover of the sampling well
(Close the cover when
measuring)
⑦
Calibration vials or sample vials
③
Display
⑧
Positioning mark (Align the mark
with the mark on the calibration
vial or the sample vial)
④
Keypad
⑨
Battery cover
⑤
Dust proof plug (Take off the plug
when measuring)
Diagram-1

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3.2 Meter and Accessories
①
Standard solution: 0.02NTU,
20.0NTU, 100NTU, 800 NTU
⑥
Silicon oil (10 ml)
②
Portable case
⑦
Sample vial×3
③
TN400 Meter
⑧
Screwdriver (to remove
battery cover)
④
Soft cloth
⑨
Instruction manual
⑤
“AA” Alkaline battery×4
Diagram-2
①
②
③
④
⑤
⑥
⑦
⑧
⑨

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3.3 Display
Measuring Mode
Calibration Mode
Calibration Menu Mode
3.4 Keypad
Diagram- 3
①— Measuring mode icon
②— reading/Unit
③— Progress bar
④— Operational directive
⑤— Low battery display
①— Calibration mode icon
②— Reading/Unit
③— Progress bar
④— Operational directive
①— Calibration mode Icon
②— Standard solution value
③— Operational directive

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Key
Functions
Power on/off
The meter will automatically shut off 10 mins after last key
press
 Initiate /Exit the calibration mode
In measuring mode：Short press the key to perform single-
shot
measurement; long press the key to perform continuous
measurement.
In calibration mode: press the key to confirm the calibration.
In calibration mode, press the key to select standard
solution.
3.5 Battery Installation
1. Use the screwdriver to remove the four screws on the battery cover and
open the battery cover.
2. Insert 4 pieces of AA alkaline battery. Please make sure the polarity is
correct.
3. Put on the battery cover and screw tightly.
4 METER CALIBRATION
TN400 turbidity meter needs to be calibrated with the provided standard
solution when used for the first time. For normal use, it is suggested to calibrate
the meter monthly or weekly depending on the frequency of use; or the user
can perform verification test, which is to test the standard solution that is close
to the value of the test sample. If the error is big, it is necessary to calibrate the
meter. To ensure the accuracy, 4 polymer standards included in the meter kit
should be selected to calibrate the meter.

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4.1 Calibration Standards
TN400 turbidity meter adopts US EPA certified Reagecon high molecular
weight polymer turbidity standard solution. Compared with traditional Formazin
standard solution, Reagecon standard solution has a lot of advantages, such
as non-toxicity, high accuracy, long shelf-life, traceable to NIST and so on. The
standard solution supplied in the TN400 turbidity meter kit has a shelf-life of 12
months (from the date of manufacture). Please check the date on the bottom
of the vials before using.
4.2 Calibration Procedure
1）Apply a little silicone oil on the
calibration vial and wipe with the soft
cloth to obtain an even distribution.
Turn the vial of 20.0, 100, 800 NTU
upside down several times and set it
still for 2 mins.(0.02 NTU doesn’t
need to be overturned)
2) Press key to turn on the
meter. The meter indicates
measuring mode.
3) Open the flip cover and put in
0.02NTU calibration vial. Align the
mark on the vial with the mark on
the sample well and then close the
cover.
4) Press key to enter into
calibration menu, and press
key to perform calibration when
cursor indicates on 0.02NTU.
5) After calibration with 0.02NTU
standard, press key to
return to calibration menu.
6) When cursor indicates on
20.0NTU, put the calibration vial of
20.0 NTU into the sample well and
press key to calibrate.

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7) After calibration with 20.0 NTU
standard, press key to
return to calibration menu.
8) When cursor indicates on
100NTU, put the calibration vial of
100NTU into the sample well and
press key to calibrate.
9) After calibration with 100 NTU
standard, press key to
return to calibration menu.
10) When cursor indicates on
800NTU, put the calibration vial of
800 NTU into the sample well and
press key to calibrate.
11) After calibration with 800 NTU
standard, press key to
confirm.
12) The meter enters measuring
mode.
4.3 Calibration Notes
1) Place turbidimeter on a flat and level surface,
and please do not hold the instrument in hand.
2) When a calibration vial is placed into measuring well, the arrow
mark on vial cap must be aligned with the arrow mark on
the measuring well. See diagram-4
3) Apply 1-2 drops of silicone oil on the calibration vial and
wipe even with soft cloth to improve light scattering. After wiping and
cleaning, set the calibration vial still on the table for at least 2 minutes to
eliminate micro bubble in solution. For 0.02 NTU calibration vial, the standing
time should be at least 5 minutes.
4) Please perform 4 points calibration for first time use according to clause
4.3. 2 to 4 points of calibration can be selected for subsequent use
according to requirement. Better result is obtained if it is in the range of
the above two points. When calibrating, press
or to select calibration standard. After calibrating, press
button to quit and enter measurement mode.
Diagram- 4