Sherwood 420 User manual

425 91 001 Issue 22 2nd December 2016 ECN 1410 & 1932
W:\DOCUMENT CONTROL\Manuals\Flame\425\42591001 M420 & M425 Operator Manual Issue 22.doc
Model 420 and Model 425
Flame Photometer
Operator Manual
Sherwood Scientific Limited
1 The Paddocks
Cherry Hinton Road
Cambridge
CB1 8DH
United Kingdom
Copyright © Sherwood Scientific Limited 2017

Model 420 & 425 Flame Photometer
425 91 001 Issue 22 1st December 2016 ECN 1410 & 1932 - 2 -
Short Form Instructions Model 420/425 Flame Photometer
The Default mode for the Model 420/425 that will appear when the instrument is
switched on is: -
Dual channel Sodium and Potassium with Peak detection and Reference
mode selected. These instructions are to be used in the default mode.
NB In Reference Mode the Blank solution, as well as the Calibration
Standard and Sample, must contain 100ppm Li (Use the Blank solution
to dilute the Standards and Samples).
Operation: -
Set Up and Ignition
1. Ensure that the ‘U’ tube is full of deionised water.
2. Connect the gas supply (maximum 30psi Propane or Butane) via a Primary
regulator.
3. Switch on the compressor and regulate the air pressure to 11psi on the
gauge at the rear of the instrument.
4. Switch on the instrument with the “1/0” switch.
5. If the flame ignites then an auto sequence will test various circuits and end
with the ‘000’ flashing in both channel displays.
6. If the flame does not ignite, switch off, wait 15 to 20 seconds and repeat
step 4. It may take 3 or 4 attempts if the instrument has not been used for
some time.
Blanking (Zeroing)
7. With the ‘000’ flashing aspirate the blank solution and press the ‘Blank’
button once.
8. The instrument will then zero to the blank values; this will take at least 30
seconds; Remove the blank when complete.
Calibration
9. When the blanking procedure is complete, the previous calibration values
that were used will appear in the displays and the ‘Cal’ indicators will flash. If
you wish to calibrate to these values go to 11.
10. If you wish to change the values use the ‘+ and –’ keys before aspirating the
standard solution.
11. Then press the Sodium ‘Set’ button, then start aspirating the standard and
press the Potassium ‘Set’ button within a few seconds.
12. Once the instrument has calibrated itself then the ‘Cal’ lights will flash;
remove the standard and press ‘Set’ on both channels again.
Measuring a Sample
13. After 5 seconds both displays will flash and the “Measure” light will
illuminate, the first sample can now be measured.
14. Aspirate the sample and then immediately press the ‘Print/Measure’ button.
15. The instrument will measure the sample until the peak algorithm captures the
value and the measure light shows continuously. Remove the sample.
16. After 5 seconds the displays will flash and the next measurement can be
made.

Model 420 & 425 Flame Photometer
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Table of Contents Page
Short Form Instructions Model 420/425 Flame Photometer ......................................................... 2
Operation: -.................................................................................................................................2
1INTRODUCTION ...............................................................................................................6
1.1 Contacting Sherwood Scientific................................................................................6
1.2 Using this manual.....................................................................................................6
1.3 Safety Precautions ....................................................................................................7
1.4 Reagents...................................................................................................................8
Reference/Lithium Standard.....................................................................................8
Blank Storage...........................................................................................................8
Purification...............................................................................................................8
1.5 Dilutions ..................................................................................................................8
Dilution Ratio......................................................................................................... 10
Urine Samples........................................................................................................ 10
1.6 BlueNotes............................................................................................................... 17
1.61 BlueNotes Software Installation…………………………………………………13
1.7 Warranty................................................................................................................ 17
2 INSTALLATION.............................................................................................................. 18
2.1 Location ................................................................................................................. 18
2.2 Services Required................................................................................................... 18
Electrical Supply.................................................................................................... 18
Fuel........................................................................................................................ 18
Air.......................................................................................................................... 18
Waste Container..................................................................................................... 18
2.3 Unpacking.............................................................................................................. 19
Accessory List ........................................................................................................ 19
2.4 Assembly................................................................................................................ 20
2.5 Connecting Peripheral Devices............................................................................... 24
Printer.................................................................................................................... 24
Computer ............................................................................................................... 24
Analogue Devices................................................................................................... 24
Auto-sampler.......................................................................................................... 24
2.6 Setting Date and Time............................................................................................ 25
2.7 Setting Filter Factors .............................................................................................. 26
2.8 Setting Units........................................................................................................... 26
2.9 Setting Sample Delay (in Peak mode)..................................................................... 27
2.10 Setting the Output Voltage ..................................................................................... 27
2.11 Setting the analogue damping coefficient................................................................ 27
3 PRINCIPLES OF OPERATION........................................................................................ 28
3.1 Application of Flame Photometry ........................................................................... 28
3.2 Principles of Flame Photometery............................................................................. 28
3.3 The Internal Standard Mode................................................................................... 29
4 PERFORMANCE CHARACTERISTICS & SPECIFICATIONS....................................... 30
4.1 Readout .................................................................................................................. 30
4.2 Measurement Ranges.............................................................................................. 30
4.3 Specificity............................................................................................................... 31
4.4 Accuracy................................................................................................................ 31
Linearity................................................................................................................. 31
Drift ....................................................................................................................... 31
Reproducibility (using Peak mode) ......................................................................... 31
Using Peak with Ref (Internal Standard) Mode....................................................... 31
4.5 Warm Up................................................................................................................ 32

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4.6 Sample Requirements............................................................................................. 32
Type....................................................................................................................... 32
Method of Presentation........................................................................................... 32
Volume................................................................................................................... 32
4.7 Chart Recorder Output............................................................................................ 33
4.8 Environmental Conditions...................................................................................... 33
Temperature........................................................................................................... 33
Humidity................................................................................................................ 33
4.9 Power Requirements............................................................................................... 33
Voltage................................................................................................................... 33
Power ..................................................................................................................... 33
4.10 Fuel........................................................................................................................ 33
4.11 Air.......................................................................................................................... 34
4.12 Size........................................................................................................................ 34
4.13 Weight ................................................................................................................... 34
5 DESCRIPTION OF INSTRUMENT.................................................................................. 35
5.1 Front Panel Controls and Indicators........................................................................35
5.1.1 Controls.......................................................................................................... 35
‘-’ ‘Set’ ‘+’ ..................................................................................................35
Blank............................................................................................................. 36
Single/Dual and Element Selection ................................................................36
Peak/Ref/Cont................................................................................................ 36
Measure......................................................................................................... 37
5.1.2 Description of Indicators................................................................................. 37
Cal (Ch1 & Ch2)............................................................................................ 37
Single ............................................................................................................ 37
Dual............................................................................................................... 37
Peak............................................................................................................... 37
Ref................................................................................................................. 37
Cont............................................................................................................... 38
Measure......................................................................................................... 38
Flame On....................................................................................................... 38
Power On....................................................................................................... 38
5.2 Rear Panel Controls and Connections..................................................................... 38
Channel 1 & 2 Data Outputs................................................................................... 39
RS232/Printer Output............................................................................................. 39
External Device Output .......................................................................................... 39
Power ..................................................................................................................... 39
Gas......................................................................................................................... 39
Air.......................................................................................................................... 39
Air Regulator.......................................................................................................... 39
5.3 Operating Modes.................................................................................................... 40
5.3.1 Single/Dual Mode........................................................................................... 40
Single ............................................................................................................ 40
Dual............................................................................................................... 40
Blanking........................................................................................................ 40
Calibration..................................................................................................... 40
5.3.2 Peak/Cont....................................................................................................... 41
Peak............................................................................................................... 41
The Peak Cycle .............................................................................................. 41
5.3.3 Ref Mode........................................................................................................ 42
Cont............................................................................................................... 42
5.3.4 Blank.............................................................................................................. 42

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6 OPERATING THE INSTRUMENT .................................................................................. 43
6.1 Start Up.................................................................................................................. 43
6.1.1 Compressor Start Up ...................................................................................... 43
6.1.2 Switch On ...................................................................................................... 43
6.1.3 Ignition Successful ......................................................................................... 43
6.2.1 Required Blanking.......................................................................................... 43
6.2.2 Required Calibration ......................................................................................44
6.3 Sample Measuring.................................................................................................. 45
6.3.1 Measuring in Peak mode ................................................................................45
6.3.2 Measuring in Continuous mode...................................................................... 45
6.4 Automatic operation ............................................................................................... 45
6.5 Sample Numbering................................................................................................. 46
6.5.1 Reset of sample number.................................................................................. 46
6.5.2 Repeat sample ................................................................................................ 46
6.5.3 QC sample...................................................................................................... 46
6.6 Shutdown Procedure............................................................................................... 46
7 OPERATING HINTS, PRECAUTIONS & LIMITATIONS............................................... 47
7.1 Hints ...................................................................................................................... 47
7.2 Operational Precautions and Limitations ................................................................ 47
7.3 Hazards.................................................................................................................. 48
7.4 Measuring Calcium ................................................................................................ 48
8 CLEANING AND MAINTENANCE PROCEDURES....................................................... 49
8.1 General................................................................................................................... 49
8.2 Daily Maintenance ................................................................................................. 49
8.3 Weekly Maintenance.............................................................................................. 49
8.4 Monthly Maintenance............................................................................................. 49
8.5 Six Monthly Maintenance....................................................................................... 50
8.6 Nebuliser................................................................................................................ 50
8.6.1 Operational Check.......................................................................................... 50
8.6.2 Cleaning the Nebuliser ................................................................................... 51
8.7 Cleaning the Mixing Chamber, Burner and Drain .................................................. 52
8.8 Cleaning the Filters and Glass Chimney................................................................. 53
8.9 Deproteinising or Disinfecting Procedure ............................................................... 54
9 ACCESSORIES, CONSUMABLES & SPARE PARTS..................................................... 55
9.1 Ordering Information ............................................................................................. 55
9.2 Spares and Accessories........................................................................................... 55
9.3 Reagents................................................................................................................. 56
APPENDIX A........................................................................................................................... 57
BIBLIOGRAPHY........................................................................................................ 57
APPENDIX B ........................................................................................................................... 58
APPENDIX C………………………………………………………………………………………60
Sherwood Scientific Product Warranty Statement......................................................................61

Model 420 & 425 Flame Photometer
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1Introduction
1.1 Contacting Sherwood Scientific
Postal address for letters and orders:
Sherwood Scientific Ltd
1 The Paddocks
Cherry Hinton Road
Cambridge
CB1 8DH
UK
Telephone [phone]
Fax [phone]
Email [e-mail]
For Certificates of Analysis and Material Safety Data Sheet downloads, contacting
Distributors and Technical and Application information on our products go to our website
www.sherwood-scientific.com
The following section must be carefully read before unpacking, installing, using, maintaining
or repairing the instrument and/or its accessories.
1.2 Using this manual
This manual is structured to allow both quick access to a measurement from
the default position of the Instrument (Section entitled Short Form
Instructions on page 2) and an in-depth understanding of the Set-up,
Operation and Maintenance of these two advanced Flame Photometers.
The information contained in this manual was correct at the time of going to print. However, Sherwood
Scientifics’ policy is one of continuous product improvement and the right to change specifications,
equipment and maintenance procedures at any time, without notice, are reserved.
This manual is copyrighted, and all rights are reserved. No part of this manual may be reproduced by
any means or in any form without prior consent in writing.

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Introduction
continued
1.3 Safety Precautions
The Model 420 and 425 are intended for use by persons knowledgeable in safe
laboratory practices. If the instruments are not used in accordance with these
“Instructions for use”, the protection provided by the equipment may be impaired.
WARNING The Model 420/425 are designed to be earthed (grounded) through
the power supply lead (line cord) for safe operation. For the safety of operating
personnel and optimum performance make sure that the instrument is only
connected to a 3-pin socket (outlet) that has an effective earth connection. If
you are in any doubt about the safety of your electrical supply system consult
a competent, qualified electrician.
There are no user replaceable parts within the instrument. Do not remove the rear
cover from the instrument.
Sherwood Scientific Limited and its authorised Distributors consider themselves responsible for the
effects of safety, reliability and performance of the Model 420/ Model 425 only if: -
** Assembly operations, extensions, re-adjustments, modifications or repairs are only carried
out by persons authorised by them.
** The electrical installation of the relevant room complies with IEC requirements or the local
regulatory code.
** The equipment is used in accordance with the instructions for use.
PLEASE NOTE that no cables neither for power-in nor for signals-out to the printer, computer
via RS232 output nor analogue to a chart recorder, nor signal cables from an Autosampler
nor any other device should exceed 2.5 metres in length.

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Introduction
continued
1.4 Reagents
Sherwood Scientific supply a wide range of reagents, including standards, diluent
and maintenance solutions, for use with the Model 420 and 425 Flame
Photometers. Please refer to Section 9.3 for a complete list of the reagents
available.
Reference/Lithium Standard
The full benefit of the technology incorporated in the Model 420/425 is utilised in the
default mode of operation. This mode, ‘Peak’ and ‘Reference’, requires that the
blank, standards and samples contain Lithium at the concentration of approximately
100ppm in the final solution that is aspirated. This is best achieved if the diluent
contains 100ppm Lithium. That is 100ml of the 1000ppm Li standard solution
supplied with the Model 420 (Part No. 001 56 622). Note: ‘Not Clinical version’
diluted to 1 litre with the diluent described in the following paragraph.
Blank Storage
All solutions should be stored away from direct sunlight, in a cool place (below
25°C/77°F), in an airtight container to prevent evapor ation and discolouration. Glass
containers should not be used, as they can affect Na concentration levels.
Prolonged exposure to the atmosphere must be avoided to prevent evaporation of
standard solutions.
Purification
No purification is required for Sherwood Scientific standard solutions.
1.5 Dilutions
The Model 420 and Model 425 are designed to accommodate the analysis of a wide
range of samples. The mode in which either instrument operates can be selected to
best match the concentration of the elements expected in the samples.
There are three modes, Industrial Mode 100, Clinical Mode 101 and Clinical Mode
102.
Clinical 101 is targeted for the analysis of clinical serum levels of Na, K and Li.
Clinical 102 mode measures Na, K and Li, but is designed for the higher expected
concentrations of Potassium in urine.
Industrial mode offers a wider concentration range for Potassium and Lithium.
The user can select the appropriate mode depending on the concentration of
elements expected in the samples. Table 1.5.1 below summarises how each mode
is designed to suit different combinations of concentrations.

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Introduction
continued
1.5 Dilutions continued
Concentration into the flame (i.e. after dilution)
Industrial Mode 100 Clinical Mode 101 Clinical Mode 102
Sodium
Range that
standard may
be set to
0.02 to 40ppm
or
0.0009 to 1.8mmol/l
or
0.0009 to 1.8mEq/l
1.00 to 10.00
&
10.0 to 199.0
10.0* to 199.0
*if the standard value of 10.0 is selected the result will be
reported to two decimal places
Potassium
Range that
standard may
be set to
0.02 to 20ppm
or
0.0005 to 0.5mmol/l
or
0.0005 to 0.5mEq/l
0.02 to 2ppm
or
0.0005 to 0.05mmol/l
or
0.0005 to 0.05mEq/l
(concentrations below
10mmol/l or 10mEq
diluted 200 times)
0.02 to 20ppm
or
0.0005 to 0.5mmol/l
or
0.0005 to 0.5mEq/l
1.00 to 10.00
&
10.0 to 199.0 1.00 to 10.00 10.00, 11.0 to 199.0
Lithium
Range that
standard may
be set to
0.05 to 20ppm
or
0.0007 to 2.9mmol/l
or
0.0007 to 2.9mEq/l
0.05 to 0.7ppm
or
0.0007 to 0.1mmol/l
or
0.0007 to 0.1mEq/l
(concentrations below 5.0mmol/l or 5.0mEq/l diluted
50 times)
1.00 to 10.00
&
10.0 to 199.0 1.00 to 5.00
Calcium
Range that
standard may
be set to
0.2 to 100ppm
or
0.005 to 2.5mmol/l
or
0.0025 to 1.3mEq/l
1.00 to 10.00 & 10.0 to 199.0
Table 1.5.1 – Selecting Mode to suit Concentration

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Introduction
continued
1.5 Dilutions continued
Check which mode the instrument is in by pressing and holding down ‘Blank’ until
100, 101 or 102 is shown in the display. Press ‘+’ or ‘-‘ in Channel 1 to toggle
between modes.
When the desired mode is displayed, press ‘Set’ in Channel 1.
200 or 201 will be displayed in Channel 1 and any Delay Time will be displayed in
Channel 2, see Section 2.9. Press ‘Set’ in Channel 1 again.
300 or 301 will be displayed in Channel 1 and the Output Voltage displayed in
Channel 2, see Section 2.10. Press ‘Set’ in Channel 1 again.
400 or 401 will be displayed in Channel 1 and the Analogue Damping Coefficient
displayed in Channel 2, see Section 2.11. Press ‘Set’ in Channel 1 again.
The instrument will return to displaying ‘000’ flashing in both channels.
Dilution Ratio
The Model 420/425 are optimised for the following Dilution Ratios: -
In Clinical Mode
Na & K both Serum and Urine*: - 1:200 with diluent described above
(including Li if used in Reference Mode).
Li (Measurement) Dilution Ratio: - 1:50.
In Non-Clinical Mode
The user should ascertain from his sample what is appropriate by reference
to the input concentrations listed in the specification in Section 4.
Urine Samples*
The Potassium content of urine samples is some 20 times that of plasma or serum.
In the past, it has been necessary to pre-dilute urine samples prior to following a
normal dilution procedure with e.g. Model 805. The design of the Model 420/425
however, minimises the need for this pre-dilution and urine samples with a
Potassium concentration of 100mmol/l or less can be treated in exactly the same
way as plasma and serum samples provided that the appropriate standard is used
to calibrate the instrument for the high Potassium value. Samples with a Potassium
level greater than 100mmol/l should be pre-diluted 1 part in 5 prior to the normal
dilution 1 part in 200.
Table 1.5.2 below shows example dilutions of standards and routine clinical
samples to bring the typical concentrations into the working ranges of the Model 420
and 425.

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Introduction
continued
1.5 Dilutions continued
Sample
type Instrument mode Blank solution Standard solution preparation Sample preparation
Na & K
in
Serum
Clinical Mode
101 with Ref
facility
1 part diluent
concentrate to 999
parts 100ppm Li
solution Sherwood Clinical
standard diluted
200 times with the
blank solution.
Dilute sample
200 times
with the blank
solution.
Clinical Mode
101 1 part diluent concentrate to 999
parts good quality
deionised water
Sherwood Clinical standard prior to dilution contains 140.0mmol/l Na & 5.00mmol/l
K, therefore, set the calibration figures: Na to 140.0 & K to 5.00. As the samples
underwent the same dilution as the standard the display shows the mmol/l results in
the original sample. Printed results show mmol/l units
Sample
type Instrument mode Blank solution Standard solution preparation Sample preparation
Na & K
in Urine
Clinical Mode
102 with Ref
facility
1 part diluent
concentrate to 999
parts 100ppm Li
solution
160mmol/l Na &
80mmol/l K
standard diluted
one part in five
then 200 times
with the blank
solution.
Dilute sample
one part in
five then 200
times with the
blank
solution.
Clinical Mode
102 1 part diluent concentrate to 999
parts good quality
deionised water
The standard contained 160mmol/l Na & 80mmol/l K prior to dilution, therefore, set
the calibration figures: Na to 160.0 & K to 80.0. As the samples underwent the same
dilution as the standard the display shows the mmol/l results in original sample
Printed results show mmol/l units
Sample
type Instrument mode Blank solution Standard solution preparation Sample preparation
Li in
serum Clinical Mode 101 or 102 1 part diluent concentrate to 999
parts good quality
deionised water
5.0mmol/l Li
standard diluted 50
times with the
blank solution.
Dilute sample
50 times with
the blank
solution.
The standard contained 5mmol/l Li prior to dilution, therefore, set the calibration
figures: Li to 5.00. As samples underwent the same dilution as the standard the
display shows the mmol/l results in the original sample.
Printed results show mmol/l units
Table 1.5.2 – Dilutions of Standards

Model 420 & 425 Flame Photometer
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Introduction
continued
1.5 Dilutions continued
Samples and standards should be diluted with the same batch of diluent, made up
of 1 part Diluent Concentrate (Part # 001 56 681) to 999 parts good quality distilled
water.
The same batch of diluent should be used to zero the Model 420 and Model 425
and to prepare dilutions of standards and samples. This will prevent variations in
water purity affecting the measurements.
Great care should be taken so that contamination does not occur when preparing
the samples and standards. Remember that the accuracy of the Model 420/425 is
dependent on the accuracy and purity of the Standards and Blank used for
calibration.
To aid the dilution of clinical samples Sherwood Scientific produce a Dilutor, the
Model 805, which automates the process and gives extremely reproducible dilution
ratios and therefore precise results.
Remember when using the Model 805 Dilutor to increase the Delay Time, see
Section 2.9.
1.6 BlueNotes
A BlueNotes CDROM is provided with this instrument for loading on a PC running
Windows and will extend the instruments capability:-
•Generate reports with sample names and method details.
•Select units of ppm, mg/l, mmol/l or mEq.
•Use either K or Li as the Internal Standard Element.
•Multipoint Calibrations enabling sample concentrations across the
detector’s dynamic range to be measured.
•All the detectors can be used to determine sample concentrations
simultaneously.
•Gains can be easily optimised for sample concentrations.
•Check and automatically correct sample results for any drift.
Full operating instructions for BlueNotes are contained on the CD.
The flame photometer can still be used without BlueNotes as a standalone
instrument.

Model 420 & 425 Flame Photometer
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Introduction
continued
1.6.1 BlueNotes Software installation
The BlueNotes 420 Software is supplied on a CD-ROM with a unique 16
character alphanumeric registration code. Insert the CD-ROM into the disk
drive of a PC. The software should auto-run and the following window
appear.
Click on Next to load the software.
Read the license agreement and click Next.

Model 420 & 425 Flame Photometer
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Introduction
continued
1.6.1 BlueNotes Software Installation continued
Record the file path that BlueNotes 420 is to be installed to for future
reference & click Next.
Click Next to begin the installation.

Model 420 & 425 Flame Photometer
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Introduction
continued
1.6.1 BlueNotes Software Installation continued
Click Close to complete the installation process. The Desktop will now show
the shortcut to BlueNotes 420:
Double-click the shortcut to start BlueNotes 420. The first time that
BlueNotes is started the License number must be entered, see below.

Model 420 & 425 Flame Photometer
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Introduction
1.6.1 BlueNotes Software Installation continued continued
Enter the License Install Key (16 alpha-numeric character code) supplied
with the software.

Model 420 & 425 Flame Photometer
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Introduction
continued
1.6.1 BlueNotes Software Installation continued
Click Help then User Guide to read or print the full BlueNotes Manual for
further comprehensive instructions.
For an easy to follow guide select Help then Presentations from the Start
page, click Getting Started with BlueNotes420 for a pdf or to start the
presentation.
1.7 Warranty
Full warranty terms are listed in Appendix to this manual.

Model 420 & 425 Flame Photometer
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2Installation
2.1 Location
WARNING Under no circumstances install the Model 420/425 beneath
overhanging cupboards. There must be at least 1 metre of clear
space above the chimney.
For optimum performance, this instrument should be installed in
accordance with the following conditions: -
2.1.1 The environment must be clean and free from dust.
2.1.2 The instrument must be placed on a strong, level worktop, free from
vibration. The Model 420/425 requires approximately 500mm x
500mm of bench space, which includes an area in front for solutions
and clearance at the rear for fuel and air tubing, with clear access to
the mains supply switch.
2.1.3. Avoid sites that expose the instrument to direct sunlight or draughts.
2.1.4. To meet the specification the ambient temperature must be within
the range +10°C to +35°C and the maximum relative hum idity must
not be more than 85%, non-condensing.
2.2 Services Required
Electrical Supply
An A.C. supply between 90V and 240V ±10%, at 50Hz or 60Hz, is required for the
Model 420 and 425. The instrument is powered from an external power supply,
which will accommodate these voltages without any need to adjust the instrument.
Fuel
A supply of Propane, Butane or Propane/Butane mixture regulated at the cylinder
to 2.1kg/cm2(30psi), flow rate at least 0.4 litres per minute.
(NB. Propane only, gives the best results for Ca on the Model 425).
Primary regulators to fit cylinders are available from Sherwood Scientific, regulators
are available as optional accessories, refer to Section 9.2.
Air
A supply of clean, dry, oil-free air at 1kg/cm2(11psi), flow rate 6 litres per minute. A
suitable air compressor is listed in Section 9.2.
Waste Container
A sink or waste container sited to the right of the instrument will ensure the
minimum length of waste tubing. Do not use a waste container with high sides, as
this will cause the drain tube to be lifted above the level of the constant head drain.

Model 420 & 425 Flame Photometer
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Installation
continued
2.3 Unpacking
1. Unpack the instrument and accessories.
NOTE The Model 420/425 weighs 9.5kg; follow safe lifting techniques.
2. Check all items for damage.
3. Check that all the items on the Accessory List have been delivered. Contact
your Sherwood Scientific distributor if you have any problems.
4. The Model 420/425 is shipped with the following items: -
Accessory List
CAT. NO. DESCRIPTION QUANTITY
001 72 043 Air tubing, nylon reinforced 2 metres
001 72 114 Fuel tubing 2 metres
400 22 002 Tube Drain - all flames up to #20585 & after
#28016 1 metre
001 53 420 Universal external power supply 1
100 99 010 Nebuliser cleaning wire, pack of 3 1 pack
001 31 076 'O' ring, spare for mixing chamber 1
420 08 102 Nebuliser 1
400 22 003 Nebuliser inlet tube, polythene, 150 mm 1
425 91 001 Operators manual M420/M425 1
926 09 052 RS232 Output Cable 1
001 08 718 'Unex' tubing clamp 4
001 56 100 Standard Solution containing l40.0mmol/l Na,
5.00mmol/l K and 1.5mmol/l Li 1 x 100ml*
001 56 603 3 Molar Lithium Standard, 1 x 100ml 1 x 100ml*
001 56 622 Lithium 1000ppm Standard, 6 x 100ml 1 pack **
001 56 620 Sodium 1000ppm Standard, 6 x 100ml 1 pack **
001 56 621 Potassium 1000ppm Standard, 6 x 100ml 1 pack **
001 56 623 Calcium 1000ppm Standard , 6 x 100 ml 1 pack ***
410 92 001 CDROM, Flame Training Guide 1
420 66 000 CD, BlueNotes 420 Software 1
* supplied with Clinical instruments.
** supplied with Industrial instruments.
*** supplied with Model 425.

Model 420 & 425 Flame Photometer
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Installation
continued
2.4 Assembly
EQUIPMENT REQUIRED: -
'Pozidriv' (cross head) screwdriver 1PT
Flat blade screwdriver.
To assemble the instrument, proceed as follows: -
1. Lift off the chimney cap from the chimney assembly and lift out the glass
chimney. Remove any packing material from inside, making sure that there
are no small pieces left within the chimney.
2. Replace the glass chimney with the clear strip at the bottom and refit the
chimney cap on top of the chimney.
3. Remove the Nebuliser (420 08 102) from its box and push the barbed
connector into the end of the air tubing (item 3, figure 2.1). Fit the Nebuliser
(item 1, figure 2.1) to the mixing chamber and position the retainer (item 2,
figure 2.1) to lock it into position. Locate the Nebuliser inlet tubing (400 22
003) and fit over the narrow tube in the front of the Nebuliser.
Figure 2.1 Mixing Chamber
1. Nebuliser, 2. Nebuliser retainer, 3. Air tubing, 4. Constant head & drain, 5. Fuel tubing,
6, End Cap, 7, Securing Screw.
4. Connect the length of rubberised fuel tubing (001 72 114) between the inlet
connector on the internal regulator, (item 5, figure 2.2) and the regulator at
the cylinder outlet connector. Secure with 'Unex' tubing clamps (001 08 718).