wtw Turb 355 IR/T User manual

Turb 355 IR/T
ba75454e03 09/2010 41
Operating Manual
Portable turbidimeter

42
Accuracy when
going to press
The use of advanced technology and the high quality
standard of our instruments are the result of a continuous
development. This may result in differences between this
operating manual and your instrument. Also, we cannot
guarantee that there are absolutely no errors in this manual.
Therefore, we are sure you will understand that we cannot
accept any legal claims resulting from the data, figures or
descriptions.
Copyright ©Weilheim 2010, WTW GmbH
Reproduction in whole - or even in part - is prohibited without
the express written permission of WTW GmbH, Weilheim.
Printed in Germany.

Inhaltsverzeichnis
43
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
1.1 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.2 Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
2.2 General safety instructions . . . . . . . . . . . . . . . . . . . 50
3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . 53
3.1 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
3.2 Initial commissioning . . . . . . . . . . . . . . . . . . . . . . . . 53
4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
4.1 Instructions for operating . . . . . . . . . . . . . . . . . . . . . 55
4.1.1 Marking and indexing cuvettes . . . . . . . . . . 55
4.1.2 Venting the sample . . . . . . . . . . . . . . . . . . . 57
4.2 Measuring turbidity . . . . . . . . . . . . . . . . . . . . . . . . . 58
4.3 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.3.1 Basic information on calibration . . . . . . . . . . 61
4.3.2 Calibration procedures . . . . . . . . . . . . . . . . 61
4.3.3 Preparing the calibration . . . . . . . . . . . . . . . 62
4.3.4 Three-point calibration . . . . . . . . . . . . . . . . . 63
4.3.5 Partial (user-defined) calibration . . . . . . . . . 66
5 Maintenance, cleaning, disposal . . . . . . . . . . 69
5.1 Changing the batteries . . . . . . . . . . . . . . . . . . . . . . 69
5.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.2.1 Cleaning the instrument . . . . . . . . . . . . . . . . 71
5.2.2 Cleaning the cuvettes . . . . . . . . . . . . . . . . . 71
5.3 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6 What to do if... . . . . . . . . . . . . . . . . . . . . . . . . . 73
7 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . 75
8 Accessories, Options . . . . . . . . . . . . . . . . . . . 77
9 Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Inhaltsverzeichnis
44

Overview
45
1Overview
The Turb 355 IR/T enables rapid and reliable turbidity
measurements to be carried out on individual samples.
The measuring method used corresponds to
DIN EN ISO 7027 (Turb 355 IR) or US EPA 180.1
(Turb 355 T).
1Cuvette in the cuvette shaft
2Marking ring for calibration standard
3Mark
4Display
5Keypad
TURB 355 IR
CA L
4283
NTU
FNU
1
2
3
4
5

Overview
46
1.1 Display
The LCD display has the following display elements:
1Calibration symbol - instrument in Calibration mode
2Error symbol - flashes when an error occurs
3Battery symbol - is illuminated if the battery needs to
be changed
4Measuring unit NTU or FNU
5Main line
13
2
4
...8
NTU
FNU
CAL ERR
123
4
5

Overview
47
1.2 Keypad
The Turb 355 IR/T has a keypad with the following 5 keys:
Key Function
Switch measuring instrument on/off
Select calibration standard
Start measurement;
press and hold: index the cell;
release again: start measurement or
calibration
Call up or terminate calibration mode
CAL

Overview
48

Safety
49
2Safety
This operating manual contains basic instructions that you
must follow during the commissioning, operation and
maintenance of the measuring instrument. Consequently,
all responsible personnel must read this operating manual
before working with the measuring instrument.
The operating manual must always be available within the
vicinity of the measuring instrument.
Target group The measuring instrument was developed for
measurements on site and in the laboratory. We assume
that, due to their professional training and experience,
operators are familiar with the safety measures that are
necessary when handling chemicals.
Symbols
used
Caution
indicates instructions that have to be followed to prevent
damage to your instrument.
Note
indicates notes that draw your attention to special features.
Note
indicates cross-references to other documents, e.g.
Application reports.

Safety
50
2.1 Authorized use
Authorized use consists exclusively of the turbidity
measurement of individual samples on site or in a laboratory
environment.
The technical specifications given in the TECHNICAL DATA
chapter must be observed. Only the operation and running
of the measuring instrument according to the instructions
given in this operating manual is authorized. Any other use
is considered unauthorized.
2.2 General safety instructions
This instrument left the factory in a technically safe and
secure condition.
Function and
operating safety
The smooth functioning and operational safety of the
measuring instrument can only be guaranteed if the
generally applicable safety measures and the specific safety
instructions that appear in this operating manual are
followed during operation.
The smooth functioning and operational safety of the
measuring instrument can only be guaranteed under the
climatic conditions specified in the chapter, TECHNICAL
DATA.
If the instrument was transported from a cold environment to
a warm environment, the formation of condensate can
impair the functioning of the instrument. In this event, wait
until the temperature of the instrument reaches room
temperature before putting the instrument back into
operation.

Safety
51
Safe operation If safe operation is no longer possible, the instrument must
be taken out of service and secured against inadvertent
operation!
Safe operation is no longer possible if the measuring
instrument
zhas been damaged in transport
zhas been stored under adverse conditions for a lengthy
period of time
zis visibly damaged
zno longer operates as described in this manual.
If you are in any doubt, please contact the supplier of the
instrument.
Obligations of the
operator
The purchaser of this measuring instrument must ensure
that the following laws and guidelines are observed when
using dangerous substances:
zEEC directives for protective labor legislation
zNational protective labor legislation
zSafety regulations
zSafety datasheets of the chemical manufacturers.

Safety
52

Commissioning
53
3 Commissioning
3.1 Scope of delivery
zTurb 355 IR or Turb 355 T handheld turbidimeter
zOperating manual
z3 calibration standards (0.02 / 10.0 / 1000 NTU/FNU)
zTwo empty cuvettes
z3 marking rings
zCleaning cloths
zCarrying case with short operating manual
z4 alkaline manganese batteries, type AAA/Micro (in the
meter)
3.2 Initial commissioning
Switching on
Note
The meter was calibrated and tested by the manufacturer
before delivery. Consequently, you can begin to measure
immediately. However, we recommend to recalibrate
following the initial commissioning (see section
4.3 CALIBRATION). Thus, you will quickly become familiar
with the operation and calibration of the meter.
1Switch on the turbidimeter: Press the 0key for
approx. one second. The instrument is immediately
ready for operation.

Commissioning
54
Display when
ready to measure
After switching on or calibrating the following display
indicates that the instrument is ready to measure:
Display during
measurement
While measuring, the instrument displays moving dashes
prior to displaying a stable measured value:
After approx. 8 - 11 seconds the measured value is
displayed:
Example of a
measured value
display
Energy saving
feature
The instrument has an energy saving feature.
The energy saving feature switches off the instrument if no
key is pressed for 5 minutes.
ERR
3
2
4
- r d -
NTU
FNU
-
CAL ERR
13
2
4
- - -
NTU
FNU
CAL ERR
13
2
4
4 2 8 3
NTU
FNU

Operation
55
4 Operation
4.1 Instructions for operating
4.1.1 Marking and indexing cuvettes
Even completely clean quality cuvettes exhibit tiny
directional differences in their light transmittance. Therefore,
if you want to achieve accurate and reproducible
measurement results, it is necessary to always index the
sample cuvettes and calibration standards in the same way
(see section 2130 of the "Standard Methods for the
Examination of Water and Wastewater", 19th edition).
Note
Never apply oily liquids (or so-called "special silicone oils")
in order to "smooth" possible scratches. They would unnec-
essarily soil the meter and your working environment. The
measurement accuracy is ensured by aligning the cuvettes.
Scratched cuvettes have to be replaced.
Cleaning the cuvette The cuvette must be absolutely clean (see section
5.2.2 CLEANING THE CUVETTES).
Indexing the sample
cuvette
A sample cuvette with screwable light protection cap is
indexed during measurement (see section 4.2 MEASURING
TURBIDITY).
Marking calibration
standards
Calibration standards with a permanently fixed light
protection cap can be permanently marked using the
marking rings provided. A marked calibration standard can
be quickly brought into the optimum position. For this
purpose, the marking rings have an arrow that is turned
towards the mark on the light shaft. This shortens the entire
calibration procedure.

Operation
56
Mark a calibration standard as follows:
Note
To keep the drift as low as possible, the time for indexing the
cuvette while pressing and holding the 1key is limited to
30 or 60 seconds. After this time the turbidimeter
automatically starts the measurement or calibration.
1Switch on the turbidimeter: Press the 0key.
2 Make sure that the outside of the cuvette is clean,
dry, and free of fingerprints.
3Insert the calibration standard in the cuvette shaft so
that it clicks into place.
4 Slowly rotate the calibration standard by one
complete rotation (by 360 °) in small steps and hold
the 1key depressed while doing so. After each
step, wait for a moment until the display is stable.
Watch the display of the turbidimeter while you rotate
the cuvette. Subsequently, turn the calibration
standard to the position with the lowest displayed
value.
5With the cuvette in this position, place a marking ring
on the calibration standard so that the arrow on the
marking ring points to the mark on the enclosure.
6 Leave the marking ring on the light protection cap of
the calibration standard. This calibration standard is
now marked permanently.

Operation
57
Indexing a
calibration standard
during calibration
A marked calibration standard is indexed as follows:
4.1.2 Venting the sample
Air bubbles in the sample affect the measuring result to a
massive extent because they have an extensive scattering
effect on the incident light. Larger air bubbles cause sudden
changes in the measured values whereas smaller air
bubbles are recorded by the instrument as turbidity.
Therefore, avoid or remove air bubbles:
Avoiding or
removing air
bubbles
zDuring sampling, ensure all movement is kept to a
minimum
zIf necessary, vent the sample (ultrasonic baths, heating or
adding a surface-active substance to reduce surface
tension)
1Insert the marked calibration standard in the cuvette
shaft so that it clicks into place.
2 Turn the calibration standard so that the arrow on the
marking ring points to the mark on the enclosure.
3While pressing and holding the 1key, slowly
align the calibration standard in the range around the
arrow, i.e. turn it in small steps. After each step, wait
for a moment until the display is stable.
Subsequently, turn the calibration standard to the
position with the lowest displayed value.
4 Leave go of the 1key.

Operation
58
4.2 Measuring turbidity
Caution
Never pour liquid directly into the cuvette shaft. Always use
a cuvette for the measurement. The measuring instrument
only measures precisely when the cuvette is closed with the
black light protective cap (WTW cuvettes).
Note
The outside of the cuvette always has to be clean, dry, and
free of fingerprints. Clean the cuvette before starting to
measure (see section 5.2.2 CLEANING THE CUVETTES). Only
hold the cuvettes by the top or by the black light protection
cap.
Measuring This is how to measure the turbidity of a sample using the
Turb 355 IR/T:
1Switch on the turbidimeter: Press the 0key.
2 Rinse out a clean cuvette with the sample to be
measured:
Pour approximately 10 ml sample into the cuvette.
Close the cuvette and rotate it several times before
throwing the sample away.
3Repeat the rinsing procedure twice more.
4 Fill the cuvette with the sample to be measured
(approx. 15 ml). Close the cuvette with the black light
protection cap.

Operation
59
Note
To keep the drift as low as possible, the time for indexing the
cuvette while pressing and holding the 1key is limited to
30 or 60 seconds. After this time the turbidimeter
automatically starts the measurement or calibration.
5Make sure that the outside of the cuvette is clean,
dry, and free of fingerprints.
6 Insert the cuvette in the cuvette shaft so that it clicks
into place.
7Align the cuvette:
Slowly rotate the cuvette by one complete rotation
(by 360 °) in small steps and hold the 1key
depressed while doing so. After each step, wait for a
moment until the display is stable. Watch the display
of the turbidimeter while you rotate the cuvette.
Subsequently, turn the cuvette to the position with the
lowest displayed value.
8Leave go of the 1key.
9 Dashes are displayed while the measured value is
being determined.
10 Read the measured value when it is displayed.
11 Repeat steps 2 to 9 for further samples.
CAL ERR
13
2
4
4 2 8 3
NTU
FNU

Operation
60
Display when
measuring range is
exceeded
If the measured value is outside the measuring range of the
Turb 355 IR/T, 1100 flashes on the display:
Switching the meter
on/off
To switch the meter off, press the 1key.
CAL
1
ERR
3
2
4
1 1 0 0
NTU
FNU