PERSEE T8DS User manual

Analytical
Instruments
for
Science
T8DS
USER MANUAL
U V -VIS SPECTROPHOTOMETER

Introduction
Thank you for your purchase of the Persee Analytics Inc. T8DS
spectrophotometer.
UV-Visible Spectrophotometer analysis is a well-accepted, documented technique with
many applications. The technique is extensively used for the analysis of agricultural products,
public health, environmental protection, life science industries and many other organic and
biochemical applications.
For obtaining maximum performance and trouble-free operation, please see the following
suggestions:
Upon receiving your instrument, please check that all the items listed in the
packing list are included and install the instrument according to the instruction
manual.
The spectrophotometer is a precise electronic instrument. Please read the
instruction manual carefully before operation. If the equipment is used in a manner
not specified by the manufacturer, the protection provided by the equipment may
be impaired.
Avoid impact and handle the instrument carefully during transportation.
If the tested solution is harmful to humans, please wear gloves or use other
protection methods.
Please keep the accessories in a safe place for the use in future maintenance.
For more information, please visit www.perseena.com

Contents
Contents ........................................................................................................................................ I
Chapter 1 Instrument Introduction............................................................................................. 1
1.1 Components inspection ................................................................................................... 1
1.2 UV/Vis spectrophotometer and method........................................................................... 1
1.2.1 UV/Vis spectrophotometer method......................................................................... 1
1.2.2 UV/Vis spectrophotometer...................................................................................... 1
1.2.3 Condition of measure method ................................................................................ 2
1.3 Components description.................................................................................................. 3
1.3.1 Front view............................................................................................................... 3
1.3.2 Rear view ............................................................................................................... 4
1.3.3 Side view ................................................................................................................ 5
1.3.4 Sample cell holder .................................................................................................. 5
1.4 Specifications .................................................................................................................. 6
Chapter 2 Installation .................................................................................................................. 7
2.1 Installation location ........................................................................................................ 7
2.2 Installation ..................................................................................................................... 7
2.3 Start ............................................................................................................................... 9
2.4 Installation performance .............................................................................................. 10
2.4.1 The accuracy and reproducibility of wavelength................................................... 10
2.4.2 Flatness of the baseline........................................................................................ 12
Chapter 3 Instrument operation ............................................................................................... 13
3.1 About double beam measurement............................................................................... 13
3.1.1 What is double beam............................................................................................ 13
3.1.2 How to use a double beam instrument ................................................................. 14
3.2 Application examples................................................................................................... 15
3.2.1 Photometric measurement example ..................................................................... 15
3.2.2 Spectrum measurement example......................................................................... 16
3.2.3 Quantitative measurement example ..................................................................... 18
Chapter 4 Optional accessories ............................................................................................... 22
4.1 CH19-1 Thermostatic cell holder ................................................................................... 22
4.2 DS19-1 Angle-changeable solid sample holder............................................................. 23
4.3 IS19-1 Integrating sphere .............................................................................................. 24
4.4 LS19-1 Long pathlength cell holder............................................................................... 25
4.5 MH19-1 Micro cell holder............................................................................................... 26
4.6 MH19-2 Ultra-micro cell holder...................................................................................... 27
4.7 MR19ˉ1 Specular reflection accessory........................................................................ 28
4.8 MS19-1 Manual 8-cell holder......................................................................................... 29
4.9 PS19-2 Sipper pump ..................................................................................................... 30
4.10S19-1 Solid sample holder ............................................................................................ 32
4.11SS19-1 Short pathlength cell holder .............................................................................. 33

4.12TR19-1 Test tube cell holder.......................................................................................... 34
Chapter 5 Maintenance ............................................................................................................. 35
5.1 Points for attention:........................................................................................................ 35
5.2 Daily care ...................................................................................................................... 35
5.3 Trouble shooting and maintenance ............................................................................... 36
Appendix 1 Light source replacement.................................................................................... 40
Replace the tungsten lamp............................................................................................ 40
Replace the Deuterium lamp ......................................................................................... 42
Appendix 2 Fuse replacement .................................................................................................. 44

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Chapter 1 Instrument Introduction
1.1Components inspection
After the instrument has been unpacked, please check carefully all the parts
provided against the packing list. In the event of error or damage, contact your local
sales agent immediately. A complete set with the instrument according to the packing
list should be supplied.
The company keeps the right to revise the packing list.
1.2UV/Vis spectrophotometer and method
1.2.1 UV/Vis spectrophotometer method
A UV/Vis spectrophotometer instrument analysis method measures the
molecular absorbance of radiation in ultraviolet and visible spectrum. The absorption
of the molecules corresponds to the excitation of valence electrons and electrons in
the molecular orbital between different electronic energy levels. The analysis methods
can be used for quantitative analysis of organic and inorganic compounds.
Lambert-Beer’s law is the basic law of radiation absorbance; it is the foundation
of spectrophotometer analysis methods. The absorbance (A) of a solution is directly
proportional to the path length (b) and the concentration (c) when the wavelength of
the incidence light is fixed. Lambert-Beer’s law states that ClA 
H
, where
H
is
the constant of proportionality, called the absorbtivity.
1.2.2 UV/Vis spectrophotometer
The UV/Vis spectrophotometer is a general purpose analysis instrument which
can be used for all types of basic spectrophotometer methods. It spectrophotometer
can be classified by single beam spectrophotometer, double beam
spectrophotometer, and double wavelength spectrophotometer according to the
difference of optical structure.
All types of UV/Vis spectrophotometers are constructed with five basic
component, they are light source, monochrometer, cell holder, detector and signal
processing system.

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1.2.3 Condition of measure method
The choice of measuring wavelength
Normally taking the wavelength which has the most absorbance as the
measuring wavelength ( max
O
) to attain the highest analysis sensitivity is called
maximum absorbance principle. The absorbance will change very little during the
wavelength’s change around the max
O
, giving a good precision. we can take the low
sensitivity measuring wavelength as the absorption peak wavelength when
measuring high concentration compounds, in order to guarantee the corrective curve
has enough linear range. If the absorption peak in the wavelength max
O
is too thin,
we can adopt a little lower sensitivity wavelength to measure the condition that
satisfies the need of analysis sensitivity, which is to decrease the deviation of Beer’s
Law.
The choice of absorbance range
Because of the instability of the light source, inaccuracy of the readings, or
alternation of lab condition in the measurement, any photometer has some measuring
error. Because the transmittance T in the absorbance law is a negative logarithm to
the concentration C, from the curve of negative logarithm we can see, the relative
error of the same transmittance in a different concentration is different. The relative
error is very big when the concentration is too high or too low, so we should choose
the correct absorbance range to reduce the relative error of the results.
In practice, we can adjust the concentration of the solution or the length of the
cell to make sure that the absorbance as in the required range.
The choice of bandwidth
Bandwidth will affect the sensitivity of the measurement and linear range of
correction curve. If the bandwidth is too wide, the monochromatic light of incidence will
be less, the correction curve will deviate from Beer’s Law, and the sensitivity will be
lower. If the bandwidth is too narrow, the gain of the instrument will be very high and
the noise will be increased. We should choose the correct bandwidth by looking at the
scan of a peak and the amount of absorption for the given standard solution to be
analysed.

1.3Components description
Figure 1.1 shows the basic T8DS instrument.
Figure 1.1 Instrument
1.3.1 Front view
The front view is shown in Figure 1.2, the name and function of all the
components are described below:
Figure 1.2 Front view

1. Instrument cover
2. Front panel of the sample compartment—standard front panel for the
sample compartment. It can be replaced when using some accessories.
3. Chassis—the steel chassis can greatly reduce vibration.
4. Instrument label
5. Sample compartment cover—Open the cover to gain access to the sample compartment.
1.3.2 Rear view
The rear view is shown as Figure 1.3, the name and function of all components are
described below:
Figure 1.3 Rear view
1. Fan
2 Foot—Shockproof rubber washer is used.
3 RS-232 interface—Communication with PC.
4 Power supply— Connect to power supply: AC 110V, 60Hz.
5Fuse 1—Can be replaced (refer to “Appendix 3 fuse replacement”).
6Fuse 2—Can be replaced (refer to “Appendix 3 fuse replacement”).
7Instrument nameplate

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1.3.3 Side view
The side view is shown as Figure 1.4, the name and function of all components is
described below:
A Leftsideview BRightsideview
Figure 1.4 Side view
1. Powerswitch
2. Light source cover—Open the cover to gain access to the light source,
For replacing the deuterium lamp and tungsten lamp (refer to “Appendix 1
light source replacement”).
1.3.4 Sample cell holder
The sample cell holder is configured according to the user’s requirements. The
general configuration is the fixed two cell holder. Other types of cell holders are
available. Please refer to “chapter 4Accessories” for detailed information.
The following figure 1.5 shows the fixed cell holder which is used as the standard
configuration. It has two standard holders which are used for the sample cell and
reference cell.
Figure 1.5 Fixed cell holders

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1.4Specifications
Figure 1-3
Item Specification
Wavelength
range 900nm190nm
Spectral
bandwidth 5nmǃ2 nmǃ1 nmǃ0.5 nmǃ0.2 nmǃ0.1nm ( 6 steps)
Resolution 0.01nm
Setting
wavelength
The start and end wavelength can be set by the span of
1nm. The goto-wavelength operation can be set by the
span of 0.1nm.
Wavelength
accuracy ±0.3nm (with built-in automatic correction)
Wavelength
reproducibility 0.1nm
Wavelength of
lamp change
Set the wavelength of lamp change within the scope of
322-392nm at 1nm interval
Photometric
system
Double beam, dynamic feedback direct ratio recording
system
Photometric
scope Absorbance: -44 Abs
Recording
scope
Absorbance: -9.9999.999 Abs
Transmittance: -999.9999.9 %T
Photometric
Accuracy
±0.002Abs (00.5Abs)
±0.004Abs (0.51.0Abs)
±0.3%T (0100%T)
Photometric
reproducibility
0.001Abs˄00.5A˅
0.002Abs˄0.51A˅
0.15 %
Stray light 0.02%T˄220nm NaI 10g/L˅
Baseline
flatness
±0.001 Abs ( scan with 850~200nm, with medium
speed, at 2nm spectrum bandwidth )
Stability 0.0004 Abs/h (2hr warm-up, kinetic scan at 500nm with
2nm spectrum bandwidth)
Noise 0.0005 Abs (500nm, with 2nm spectrum bandwidth)
0.2ˁ(500nm with 2nm spectrum bandwidth)
Note:
1. The above specifications are taken with a 2nm spectrum
bandwidth. The specification may vary with different bandwidths
2. The above specifications are subject to change without notice.