Buchi C-640 User manual

UV-Vis Detector C-640
Operation Manual
11593492C en

Imprint
Product Identification:
Operation Manual (Original), UV-Vis Detector C-640
11593492C en
Publication date: 06.2016
BÜCHI Labortechnik AG
Meierseggstrasse 40
Postfach
CH-9230 Flawil 1
E-Mail: [e-mail]
BUCHI reserves the right to make changes to the manual as deemed necessary in the light of experience; espe-
cially in respect to structure, illustrations and technical detail.
This manual is copyright. Information from it may not be reproduced, distributed, or used for competitive purpos-
es, nor made available to third parties. The manufacture of any component with the aid of this manual without
prior written agreement is also prohibited.

Table of contents
3
C-640 Operation Manual, Version C
Table of contents
1 About this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2 Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.1 User qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Proper use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Improper use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Safety warnings and safety signals used in this manual . . . . . . . . . . . . . . . . . 7
2.5 Product safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
2.5.1 General hazards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
2.5.2 Safety measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.5.3 Built-in safety elements and measures . . . . . . . . . . . . . . . . . . . . . . . . 10
2.6 General safety rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1 Scope of application and delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1.1 Standard instrument. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1.2 Standard equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2 Recommended spare parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.3 Technical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.4 Configuration of the analog cinch output . . . . . . . . . . . . . . . . . . . . . . . 15
3.5 Light sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.5.1 Deuterium lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.5.2 Halogen lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.6 Signals and parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.1 Light intensity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.2 Range of wavelength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.3 Optical and electronical half width – spectral resolution . . . . . . . . . . . . . . . . 16
3.6.4 Time constant / data filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.5 Analog range ratio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.6 Display brightness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.7 Subscription / Remote or local control. . . . . . . . . . . . . . . . . . . . . . . . . 16
3.6.8 Scanning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4 Description of function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1 Front panel of the instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1.1 LED status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1.2 Icons on the graphical display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.1.3 Push-buttons of the front panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Read this manual carefully before installing and running your system and note the safety precautions
in chapter 2 in particular. Store the manual in the immediate vicinity of the instrument, so that it can be
consulted at any time.
No technical modifications may be made to the instrument without the prior written agreement of
BUCHI. Unauthorized modifications may affect the system safety or result in accidents.
This manual is copyright. Information from it may not be reproduced, distributed, or used for competi-
tive purposes, nor made available to third parties. The manufacture of any component with the aid of
this manual without prior written agreement is also prohibited.
If you need another language version of this manual, you can download available versions
at www.buchi.com.

Table of contents
4
C-640 Operation Manual, Version C
4.2 Connections at the rear panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3 The cell compartment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.3.1 Removing the cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.3.2 Mounting the cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5 Putting into operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.1 Installation site. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.2 Installing the Detector C-640 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2.1 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2.2 Connecting the communication cable . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2.3 Connecting the tubing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.3 Starting the detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.4 Controlling the detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.4.1 The start up screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.4.2 Switching the lamp on / off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.4.3 Measuring / Zeroing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.5 Parameter setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.5.1 Wavelength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.5.2 Time constant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.5.3 Half width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.5.4 Analog range ratio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.5.5 Display brightness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.6 Getting information and scanning . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.6.1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.6.2 Intensity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.6.3 Calibration menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.6.4 Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6 Maintenance and repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.1 Customer service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.2 Housing condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.3 Cleaning and replacement of the cell windows . . . . . . . . . . . . . . . . . . . . 32
6.3.1 Cleaning the cell window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.3.2 Replacing the cell windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.4 Replacement of the deuterium lamp. . . . . . . . . . . . . . . . . . . . . . . . . . 35
7 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.1 Internal display error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.2 Hardware error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
8 Shutdown, storage, transport and disposal . . . . . . . . . . . . . . . . . . . . . . . . 39
8.1 Storage and transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
8.2 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9 Declarations and requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.1 FCC requirements (for USA and Canada) . . . . . . . . . . . . . . . . . . . . . . . 40

1 About this manual
5
C-640 Operation Manual, Version C
1 About this manual
This manual describes the UV-VIS Detector C-640. It provides all information required for its safe
operation and to maintain it in good working order. It is addressed to laboratory personnel in particular.
Abbreviations
FEP Fluorelastomer
PTFE Polytetrafluoroethylene (Teflon)

2 Safety
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C-640 Operation Manual, Version C
2 Safety
This chapter points out the safety concept of the instrument and contains general rules of behavior
and warnings from direct and indirect hazards concerning the use of the product.
For the users safety all safety instructions and the safety messages in the individual chapters shall
strictly be observed and followed. Therefore, the manual must always be available to all persons
performing the tasks described herein.
2.1 User qualification
The instrument may only be used by laboratory personnel and other persons, who on account of
training and professional experience know the dangers, which can develop when operating the
instrument.
Untrained personnel or persons, who are currently being trained, require careful supervision by a
qualified person. The present Operation Manual serves as a basis for training.
2.2 Proper use
The UV-VIS Detector C-640 has been designed and built as laboratory instrument.
It is able to detect and measure changes in the light absorption behavior of liquids passing through the
flow cell of the instrument. The absorption for four selected wavelengths is measured simultaneously
and scanning over the entire wavelength range of the detector (200 – 840 nm) becomes possible in
conjunction with the BUCHI SepacoreControl software and the control unit C-620.
A deuterium lamp acts as primary light source of the instrument, supported by a halogen lamp as
secondary light source. The communication between the C-620 control unit and the SepacoreControl
software is done via a serial RS232 cable (contained in the standard equipment). If the C-640 detector
shall be used without the C-620 control unit, it can be connected directly to the C-660 fraction
collector using the cinch cable.
If the instrument is used with potentially toxic or hazardous substances, it has to be installed inside a
closed fume hood or glove box. In such case, the complete processing and system handling has to
be performed within the ventilated box to avoid toxication and other hazardous situations to the user
and the environment.
2.3 Improper use
Applications not mentioned in section 2.2 are considered to be improper. Applications which do not
comply with the technical data (see section 3 of this manual) are also considered to be improper.
The operator bears the sole risk for any damages or hazards caused by improper use!
The following uses are expressly forbidden:
• Installation or use of the instrument in rooms, which require ex-protected instruments.

2 Safety
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C-640 Operation Manual, Version C
2.4 Safety warnings and safety signals used in this manual
DANGER, WARNING, CAUTION and NOTICE are standardized signal words for identifying risk levels,
related to personal injury and property damage. All signal words, which are related to personal injury
are accompanied by the general safety sign.
For your safety it is important to read and fully understand the below table with the different signal
words and their definitions!
Sign Signal word Definition Risk level
DANGER Indicates a hazardous situation which, if not avoided, will result in
death or serious injury. ★★★★
WARNING Indicates a hazardous situation which, if not avoided, could result
in death or serious injury. ★★★☆
CAUTION Indicates a hazardous situation which, if not avoided, may result
in minor or moderate injury. ★★☆☆
no NOTICE Indicates possible property damage, but no
practices related to personal injury.
★☆☆☆
(property damage only)
Supplementary safety information symbols may be placed in a rectangular panel on the left to the
signal word and the supplementary text (see below example).
Space for
supplementary
safety
information
symbols
!SIGNAL WORD
Supplementary text, describing the kind and level of hazard/ risk seriousness.
• List of measures to avoid the herein described, hazard or hazardous situation.
• ...
• ...
Table of supplementary safety information symbols
The below reference list incorporates all safety information symbols used in this manual and their
meaning.
Symbol Meaning
General warning
Electrical hazard

2 Safety
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C-640 Operation Manual, Version C
Explosive gases, explosive environment
Harmful to live-forms
Device damage
Wear laboratory coat
Wear protective goggles
Wear protective gloves
Additional user information
Paragraphs starting with NOTE transport helpful information for working with the device / software or
its supplementaries. NOTEs are not related to any kind of hazard or damage (see example below).
NOTE
Useful tips for the easy operation of the instrument / software.

2 Safety
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C-640 Operation Manual, Version C
2.5 Product safety
Safety warnings in this manual (as described in section 2.4) serve to make the user alert and to avoid
hazardous situations emanating from residual dangers by giving appropriate counter measures.
However, risks to users, property and the environment can arise when the instrument is damaged,
used carelessly or improperly.
2.5.1 General hazards
The following safety messages show hazards of general kind which may occur when handling the
instrument. The user shall observe all listed counter measures in order to achieve and maintain the
lowest possible level of hazard.
Additional warning messages can be found whenever actions and situations described in this manual
are related to situational hazards.
!Warning
Death or serious injuries by use in explosive environments.
• Do not operate the instrument in explosive environments.
• Do not operate the instrument with explosive gas mixtures.
!Warning
Death or serious poisoning by contact or incorporation of harmful substances at use.
!Warning
Death or serious injuries by contact with high voltage.
• Only open the housing of the product when instrument is switched off and unplugged.
Notice
Risk of instrument short-circuits and damage by liquids.
• Do not spill liquids over the instrument or parts of it.
• Wipe off any liquids instantly.
• Do not move the instrument when it is in use.
• Keep external vibrations away from the instrument.

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C-640 Operation Manual, Version C
Notice
Risk of instrument damage by wrong mains supply.
• External mains supply must meet the voltage given on the type plate.
• Check for sufficient grounding.
2.5.2 Safety measures
Always wear personal protective equipment such as protective eye goggles, protective clothing, and
gloves when working with the instrument.
2.5.3 Built-in safety elements and measures
High voltage and electrostatic charges
• Safety current limitation.
• Grounded housing to arrest electrostatic charges.
2.6 General safety rules
Responsibility of the operator
The head of laboratory is responsible for training his personnel.
The operator shall inform the manufacturer without delay of any safety-related incidents which might
occur during operation of the instrument. Legal regulations, such as local, state and federal laws
applying to the instrument must be strictly followed.
Duty of maintenance and care
The operator is responsible for the proper condition of instrument at use and that maintenance,
service and repair jobs are performed with care and on schedule by authorized personnel only.
Spare parts to be used
Use only genuine consumables and genuine spare parts for maintenance to assure good system
performance and reliability. Any modifications to the spare parts used are only allowed with the prior
written permission of the manufacturer.
Modifications
Modifications to the instrument are only permitted after prior consultation with and with the written
approval of the manufacturer. Modifications and upgrades shall only be carried out by an authorized
BUCHI technical engineer. The manufacturer will decline any claim resulting from unauthorized modifi-
cations.

3 Technical data
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C-640 Operation Manual, Version C
3 Technical data
This chapter introduces the reader to the instrument and its specifications. It contains the scope of
delivery, technical data, requirements and performance data.
3.1 Scope of application and delivery
The UV-VIS Detector C-640 is available as powerful detector for the Sepacore system. It can be used
in conjunction with the SepacoreControl software, connected to the C-620 control unit or without the
use of the software, connected to the C-660 fraction collector.
The instrument can measure the change of the absorption behavior of a sample at four selected
wavelengths in the range of 200 to 840 nm.
In conjunction with the SepacoreControl software it is also able to scan the whole range of the spec-
trum continuously.
The scope and completeness of delivery can be checked according to section 3.1.2 Standard equip-
ment. After unpacking please check the instrument and all accessories thoroughly for any damages!
NOTE
For additional information about the listed products, see www.buchi.com or contact your local dealer.
3.1.1 Standard instrument
Table 3-1: Standard instrument
Product Order no.
UV-VIS Detector C-640
with preparative flow cell
11058148
Complete UV-VIS Detector C-640 system for use
in conjunction with the SepacoreControl software.
Complete with preparative flow cell, necessary cables
fittings and tubing.

3 Technical data
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C-640 Operation Manual, Version C
3.1.2 Standard equipment
Each part listed with an order number can be ordered separately as spare part.
Table 3-2: Standard equipment
Product Order no.
UV-VIS detector unit C-640
Preparative flow cell for C-640 11057949
Fitting and ferrule 1/8” (2 pcs. each) 044261
Fitting and ferrule 1/16” (2 pcs. each) 044262

3 Technical data
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C-640 Operation Manual, Version C
FEP tube inner diameter 1/16”, outer
diameter 1/8”
044354
FEP tube inner diameter 1/32”, outer
diameter 1/16”
044357
Test cell for preparative cell
Cinch cable (2 pcs.)
For connecting the C-640 directly to the
C-660 fraction collector without using the
SepacoreControl software.
045216
Power cord
RS232 cable
3.2 Recommended spare parts
Table 3-3: Recommended spare parts
Product Order no.
Deuterium lamp for C-640 11058131
Spare part set preparative flow cell 11058231

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C-640 Operation Manual, Version C
3.3 Technical specifications
Table 3-4: Technical specifications
Average power consumption max. 90 W
Power supply voltage 100–240 VAC ± 10%
Frequency 50 / 60 Hz
Fuse 2.5 A / 250 V
Dimensions (w ×d ×h) 135 ×418 ×185 mm
Weight 6 kg
Wavelength range 200–840 nm (256 elements on CCD)
Typical spectral half width 10 nm
Accuracy of adjustment ± 1 nm
Reproducibility ± 0.5 nm
Noise level at test cell ± 5 x 10-5 AU at 254 nm, TC 0.75 s
Drift at test cell (254 nm after 1 h) 1 x 10-3 AU/h
Time constant (T90) 0.5 s ; 0.75 s; 1 s or 2 s
Light source Deuterium discharge lamp / halogen lamp
Maximum flow rate 500 mL/min
Maximum pressure at the cell 20 bar / 290 psi
Output for integrator 1 V/AU (in digital form only)
Interface RS232
Installation category II
Degree of protection IP20
Pollution degree 2
Environmental conditions:
Temperature 5–40 °C for indoor use only
Altitude up to 2000 m
Humidity max. relative humidity 80% for temperatures up to
31 °C, linearly decreasing to 50% at 40 °C
Table 3-5: Material and Approvals
Materials in contact with mobile phase PTFE / fused silica / stainless steel
Approvals CE, CSA

3 Technical data
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C-640 Operation Manual, Version C
3.4 Configuration of the analog cinch output
a Analog Output (HI)
Absorbance signal output. Voltage magnitude cor-
responds to the actual absorbance in the cell. The
conversion factor depends on the settings. Output
range is from -0.2 V to 1.2 V. The analog output is
single ended.
b GNA (Low)
Analog ground of the output signal. The analog
ground is connected to the instrument housing.
Figure 3-1: Configuration of the cinch outputs (female)
3.5 Light sources
3.5.1 Deuterium lamp
The primary light source of the detector C-640 is a deuterium lamp with an average lifespan of about
1000 operating hours.
A lamp test can be performed across the whole range of the detectable spectrum (Scan) or on the
four selected wavelengths of the detection channels (A–D) only.
Note
Aging of the deuterium lamp is correlated to the measured wavelengths, e.g. if the lamp is mainly
used in the range of 200 to 250 nm, the lifespan will be reduced.
To perform the test, assemble the black test cell to the cell compartment and measure the light inten-
sity. The result can be interpreted according to the following table:
Measured light intensity Meaning Solution
> 50% Lamp is in good condition. No replacement of the lamp required.
> 10% but < 50% Lamp is working, but noise and drift of the
system may be higher. Starting the lamp
might get more and more problematic.
The lamp may be replaced to minimize
noise and drift. As soon as starting prob-
lems with the lamp occur, a replacement
of the lamp becomes necessary.
< 10% Lamp is at the end of its lifespan. The lamp needs to be replaced. (See
chapter 6.4 “Replacement of the deute-
rium lamp”.)
3.5.2 Halogen lamp
The secondary light source of the instrument is a halogen lamp. This lamp is always used together
with the deuterium lamp. Even if this lamp has a very big lifespan, a replacement of this lamp may
become necessary. A check for any damages is carried out during each initialization of the halogen
lamp. The replacement of the halogen lamp can only be performed by a specialist. Please contact
your local service.

3 Technical data
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C-640 Operation Manual, Version C
3.6 Signals and parameters
3.6.1 Light intensity
The light intensity of a newly installed lamp used with the test cell is set to 100% on all wavelengths.
These values form the reference for later tests of the light intensity.
3.6.2 Range of wavelength
The wavelength range of the detector C-640 depends on the assembly of the optical parts, the
calibration results and the number of elements of the CCD sensor that are used at the same time for
processing (“electronic half width of wavelength”)
The default electronic half width of wavelength (HF = 4) results in a wavelength range from 200 to 840
nm. Increasing of the electronic half width of wavelength (HF) can decrease the wavelength range
(symmetric for both sides of the spectrum).
3.6.3 Optical and electronical half width – spectral resolution
The base spectral resolution of the detector is based on the placement of each element of the CCD
sensor according to the placement of the lamp spectrum and the slit width. It is about 0.85 nm per
element while the slit width is a multiple of the size of one element. The slit width of the detector is 8 nm.
Multiple elements of the CCD sensor are used for signal processing at once. The total length of the
processing elements for one wavelength will affect the spectral resolution in a negative way. On the
other hand it will improve the dynamic range reduce the noise of the system. For these reasons the
adaption of the number of processing elements (“electronic half width of wavelength”) is optional
while the default value HF = 4 (8.4 nm) corresponds to the slit width and has a minimal effect on the
spectral resolution.
3.6.4 Time constant / data filtering
Processing of the raw absorbance signals is done according to the time constant of the detector.
Therefore a classic continuous time filtering is used. This kind of processing is done only for absor-
bance data but not for intensities or scanning of absorbance and intensities. For absorbance scans a
special low level time constant is used. Available values are 0.5 s, 0.75 s, 1.0 s and 2.0 s.
3.6.5 Analog range ratio
The available values are: 0.05 AU/V, 0.1 AU/V, 0.25 AU/V, 0.5 AU/V, 1 AU/V, 2 AU/V, 3 AU/V, and 5
AU/V.
3.6.6 Display brightness
The brightness of the display can be adapted to the following values:
12.5%, 25%, 37.5%, 50%, 62.5%, 75%, 87.5% and 100%.
3.6.7 Subscription / Remote or local control
Remote control means the device is controlled via the RS232 interface. Local control means the
detector is controlled using the keyboard and the graphical display of the detector itself.
Remote control starts immediately after the receipt of the first command via the RS232 interface and
is stopped after a time period of 4 seconds without any new command. For permanent remote control
a continuous communication with the detector (e.g. reading detector status) has to be established.
During subscription or remote control the instrument keyboard is locked but the graphical display still
shows the current measurement data.

3 Technical data
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C-640 Operation Manual, Version C
3.6.8 Scanning
Scanning over the whole detection range causes a high workload on the detector and its communica-
tion lines. To keep the workload for the instrument as low as possible the sample measurement of the
four predefined wavelengths for the four analog outputs is omitted during a scan. This means during a
scan the measured values on to the analog outputs will not be updated - instead the last values from
the time before the scan started will be passed on till the scan is finished.
Note
The scanning functionality is only available if the detector is controlled by the SepacoreControl soft-
ware.

4 Description of function
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C-640 Operation Manual, Version C
4 Description of function
This chapter explains the basic working principle of the UV-VIS Detector C-640. It also shows how the
instrument is structured and provides a general functional description of its assembly.
4.1 Front panel of the instrument
The front panel of the instrument consists of nine push buttons , two LED indicators bthe ON /
OFF switch a and the graphical display .
1
4
2
3
a Power switch ON / OFF
b LED indicators (Lamp = green and Error = red)
Push buttons for operating the instrument
 Graphical display
Figure 4-1: Front panel of the instrument
4.1.1 LED status
LED LED status Description
 LAMP Off The detector-lamp is off.
On The lamp is on.
NOTE
During start-up of the detector all LEDs will be switched on for a
short period of time.
Blinking The detector-lamp is starting up.
 ERROR Off The detector has no error.
On An error occurred.
NOTE
During start-up of the detector all LEDs will be switched on for a
short period of time.
Blinking Indicates a display error.

4 Description of function
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C-640 Operation Manual, Version C
4.1.2 Icons on the graphical display
Icon Meaning
If this icon of a small key is visible on the upper right corner of the display, the detec-
tor is remote-controlled by the software SepacoreControl while the communication
with the detector is established and the initial setup is performed. In this mode the
keypad of the detector is locked.
sWhile the detector is controlled by the software and measured values are transferred
from the detector to the software, the detector is running in “subscription mode”, sig-
nalized by a small “s” in the upper right corner of the display. In this mode the keypad
of the detector is locked.
4.1.3 Push-buttons of the front panel
Push-button Function
 Right Navigate right or jump to next subparameter.
 Left Navigate left or jump to previous subparameter.
 Up Navigate up or increase parameter value.
 Down Navigate down or decrease parameter value .
 ENTER Confirm Setting.
LAMP Switch detector lamp On / Off.
ZERO Start the autozero function.
MENU Enter configuration menu or navigate to next parameter.
ESCAPE Leave menu or cancel operation.
4.2 Connections at the rear panel
2
1
3
• a Main power connector with integrated
fuse (T 2.5 A)
• b RS 232 connector for connection to
the C-620 control unit
•  4 cinch connectors for analog
connection to fraction collector
Figure 4-2: Rear panel of the instrument

4 Description of function
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C-640 Operation Manual, Version C
4.3 The cell compartment
The cell compartment is located on the right side of the instrument:
Figure 4-3: Cell compartment of the C-640
The cell itself is accessible from the right side of the instrument by opening the shutter which at the
same time functions as a quick clamping lever for holding the cell in place within the optical path.
Notice
Risk of instrument damage by wrong handling.
• Make sure you always place one hand underneath the cell when opening the shutter to
prevent the cell from falling down while it is released! (The correct proceeding can be taken
from the pictures in the following section.)