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GBC Scientific Equipment Atomic Absorption Spectrophotometer Systems
SavantAA
SavantAA Zeeman SensAA XplorAA
Pre-installation Guide
December 2010 Part Number 01-0041-07
Copyright GBC Scientific Equipment Pty Ltd © 2010 All rights reserved
Information in this document is subject to change without notice and does not represent a commitment on the part of GBC Scientific Equipment Pty Ltd.
No part of this publication may be reproduced, distributed, transmitted, stored in a retrieval system, or reduced to any electronic medium without the prior consent of GBC Scientific Equipment Pty Ltd.
GBC Scientific Equipment Pty Ltd assumes no responsibility for any errors that may appear in this document or any damages arising out of the use or inability of this document.
GBC Scientific Equipment Pty Ltd acknowledges the various trademarks and proprietary names of companies and products mentioned in this document. GBC Scientific Equipment Pty Ltd is not affiliated with any of these organizations. No approval or endorsement by the organizations mentioned is intended or given either expressly or by implication.
GBC Scientific Equipment Pty Ltd reserves the right to change any in part or all specifications without prior notice.
Each GBC instrument has a unique serial number.
Printed in Australia GBC Part Number: 01-0041-07 Revision Number: 7 Issue Date: December 2010
GBC Scientific Equipment Pty Ltd
A.C.N. 005 472 686 2-4 Lakewood Boulevard Braeside, Victoria 3195, AUSTRALIA
Telephone: 61 3 9588 6666 Facsimile: 61 3 9588 6677 URL: http://www.gbcsci.com Email: gbc@gbcsci.com
GBC AAS Pre-installation Guide 3
Table of contents
Table of contents
4 GBC AAS Pre-installation Guide
TABLE OF CONTENTS............................................................................................. 3 About this manual... .............................................................................................................................................. 6 What is involved in pre-installation?................................................................................................................... 6 The customer’s responsibility .............................................................................................................................. 6 EQUIPMENT OVERVIEW.......................................................................................... 7 SavantAA............................................................................................................................................................... 8 SavantAA Zeeman ................................................................................................................................................ 8 SensAA................................................................................................................................................................... 8 XplorAA................................................................................................................................................................. 8 Accessories for SavantAA, SavantAA Zeeman, SensAA and XplorAA........................................................... 9
SDS720 X-Y-Z sample delivery system............................................................................................................. 9 System 5000 ....................................................................................................................................................... 9 HG3000 .............................................................................................................................................................. 9 EHG3000............................................................................................................................................................ 9 MC3000.............................................................................................................................................................. 9
SAFETY PRACTICES.............................................................................................. 11 Cylinders.............................................................................................................................................................. 12 Acetylene.............................................................................................................................................................. 13 Waste collection................................................................................................................................................... 13 Earthing ............................................................................................................................................................... 14 Other precautions ............................................................................................................................................... 14 SITE PREPARATION .............................................................................................. 15 Location ............................................................................................................................................................... 16 Exhaust requirements......................................................................................................................................... 19 Power requirements............................................................................................................................................ 22 Gas requirements ................................................................................................................................................ 22
Acceptable pressure and flow ranges................................................................................................................ 22 Gas purifier unit................................................................................................................................................ 23
Water requirements for analytical analysis...................................................................................................... 23 Ambient requirements........................................................................................................................................ 23 SAVANTAA ZEEMAN AAS..................................................................................... 25 Power requirements............................................................................................................................................ 26 Cooling water requirements............................................................................................................................... 26 SDS720/PS720 SAMPLE DELIVERY SYSTEM...................................................... 29 Site preparation................................................................................................................................................... 30 Power requirements............................................................................................................................................ 30 Ordering information ......................................................................................................................................... 30 SYSTEM 5000 GRAPHITE FURNACE.................................................................... 31
Table of contents
GBC AAS Pre-installation Guide 5
Location ............................................................................................................................................................... 32 Power requirements............................................................................................................................................ 32 Gas requirements ................................................................................................................................................ 33 Cooling water requirements............................................................................................................................... 33 HG3000 HYDRIDE GENERATOR ........................................................................... 35 Location ............................................................................................................................................................... 36 Dimensions........................................................................................................................................................... 36 Exhaust requirements......................................................................................................................................... 36 Power requirements............................................................................................................................................ 36 Gas requirements ................................................................................................................................................ 37 Drain requirements............................................................................................................................................. 37 EHG3000 (99-0237-11) ....................................................................................................................................... 37 MC3000 (99-0245-11).......................................................................................................................................... 37 GAS PURITY SPECIFICATIONS FOR AAS GASES .............................................. 39 Normal compositions (flame and furnace gases) .............................................................................................. 40
About this manual
6 GBC AAS Pre-installation Guide
About this manual...
This manual has been prepared to advise the customer of the pre-installation requirements for the GBC range of atomic absorption spectrophotometers and accessories.
What is involved in pre-installation?
Pre-installation involves provision by the customer of an adequate site and all ancillary services required for the operation of the instrument and its accessories.
Please read this manual carefully and ensure that all the requirements are completed prior to delivery of your system. This will enable a trouble-free installation and commissioning of the instrument.
The customer’s responsibility
It is the customer’s responsibility to provide and install:
a. Electrical power outlets.
b. Gas cylinders, regulators and plumbing.
c. Exhaust/venting system above the instrument.
d. Suitable bench space.
e. Adequate water supply for the SavantAA Zeeman/System 5000.
f. A suitable environment with respect to ambient temperature range, humidity range, and freedom from corrosive vapours and dust.
Detailed requirements are set out on the following pages. If you have any questions about any of the site requirements please contact your GBC representative.
If all requirements are not satisfied and delays in installation/commissioning occur, additional charges at the normal hourly service rate could apply.
GBC AAS Pre-installation Guide 7
Equipment overview
Equipment overview
8 GBC AAS Pre-installation Guide
SavantAA
The SavantAA double beam spectrometer incorporates automatic wavelength and slit setting and an eight-lamp automatic turret. It is controlled by an external IBM compatible computer with a hard disk drive and a high resolution colour monitor.
SavantAA Zeeman
The SavantAA Zeeman combines the longitudinal Zeeman-effect with an optimized magnetic field strength, transverse heating of the graphite tube to give a superior graphite furnace AAS instrument. It is controlled by an external IBM compatible computer with a hard disk drive and a high resolution colour monitor.
SensAA
The SensAA dual beam compact spectrophotometers are controlled by an internal computer. They feature multi-element capability with the GBC Application Source, automatic wavelength and slit setting, Hyper-Pulse background correction and interlocked (or optional automatic) flame control. A full range of flame or furnace accessories is available.
XplorAA
The GBC XplorAA AAS is designed for harsh environments. The XplorAA has specialized corrosive-resistant materials and coatings used in the sample introduction area. Some models can have a positive air pressure applied to the instrument chassis to prevent the ingress of corrosive dust/vapours to the optics and electronics areas. See page 24 for air supply requirements.
Equipment overview
GBC AAS Pre-installation Guide 9
Accessories for SavantAA, SavantAA Zeeman, SensAA and XplorAA
SDS720 X-Y-Z sample delivery system
The SDS720 is a programmable transverse (X-Y-Z) sampler with a capacity of up to 360 samples in four racks plus ten standards. There is an optional rack extension available allowing up to 720 samples. It is controlled by the GBC AAS software. Installation and operation details are contained in a separate manual supplied with the auto sampler.
System 5000
The System 5000 is an automated graphite furnace (GF5000) complete with auto sampler (PAL), which may be added for parts-per-billion trace element analysis.
HG3000
An optional automatic vapour generation accessory, the HG3000 Hydride Generator is available for achieving parts-per-billion analysis of mercury and the hydride-forming elements.
EHG3000
The EHG3000 electric heater is an accessory to the HG3000 which replaces flame-heating of the absorption cell with electrical-heating. It is powered by a separate power supply which provides temperature setting controls.
MC3000
The Mercury Concentrator is an accessory to the HG3000 which allows parts-per-trillion analysis of mercury by amalgamation with gold and subsequent liberation of the mercury by rapid heating via induction heating. The heating coil is powered by a separate power supply.
Equipment overview
10 GBC AAS Pre-installation Guide
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GBC AAS Pre-installation Guide 11
Safety practices
Safety practices
12 GBC AAS Pre-installation Guide
Cylinders
CAUTION: Compressed gases should always be handled with care and in strict accordance with the gas manufacturer’s instructions.
Installation of cylinders is preferred outside the building. If this is impractical, adequate ventilation is needed.
Always fasten cylinders to walls or other solid fixtures in a vertical position.
Do not allow any electrical arc to be struck on or adjacent to cylinders. Keep cylinders away from flame cutting operations. Keep cylinders cool.
Pipe gas with care, avoiding damage to piping, and install pressure relief valves and over-pressure protection devices. Ensure that materials used are compatible with the gas.
Shut off the gas supply at the cylinder for storage overnight, and drain the lines.
CAUTION: Drain the air line last, to remove possible mixtures of nitrous oxide and acetylene remaining in instrument.
Always use the correct cylinder. IF NOT SURE, DO NOT USE IT.
Use only approved regulators and hose connections (GBC provides Swagelok® fittings and high pressure nylon hose, which are the best quality available).
Avoid leaks, periodically test lines and fittings with a weak soap solution or Snoop®.
WARNING: Do not use a flame for leak testing.
Safety practices
GBC AAS Pre-installation Guide 13
Acetylene
Use only instrument grade acetylene.
Acetylene is a highly flammable, colourless gas of distinct odour. The high solubility of acetylene in acetone (300:1 by volume at 1100 kPa) enables it to be supplied dissolved in acetone. Acetylene cylinders are filled with porous material which carries the acetone, therefore;
CAUTION: Acetylene cylinders must not be used at cylinder pressures below 500 kPa. Doing so could allow acetone to enter the fuel line and cause damage to the instrument.
Acetylene, in its free state under pressure, may decompose with explosive violence, therefore;
WARNING: Never pipe acetylene at pressures exceeding 100 kPa (14 psi).
The following materials shall not be used for piping, fittings or any other parts intended to be in contact with acetylene:
a. Copper and copper alloys with a copper content of more than 70%.
b. Copper alloys (even with a copper content of less than 70%) in the case of filters and sieves.
c. Silver and silver alloys, except for brazing. Silver filler used for brazing shall have a silver content of less than 43%, and a copper content of less than 21%. The width of a solder gap, where silver filler might come into contact with acetylene, shall be less than 0.3 mm.
d. Any other material which may form an explosive acetylide.
Waste collection
Liquid wastes should be fed into a large plastic (NOT GLASS) container placed under the bench beneath the AAS. The container should be wide open-necked, and MUST NOT be located in a closed cupboard. It is vital that there be free ventilation around and within the container.
It may be necessary to drill through the bench top to allow for drain hoses.
An alternative is an appropriately designed and constructed drainage system that achieves the above safety requirements.
CAUTION: Do not allow acids and solvents to mix.
Safety practices
14 GBC AAS Pre-installation Guide
Earthing
The earth terminal of the power outlet to be used for any GBC equipment should be suitably connected to the earth.
WARNING: Failure to observe this may endanger the user’s life and will void the instrument warranty.
The earth conductor size should be 2.5 mm2 minimum, or, for a graphite furnace system, the same size as used for the active and neutral wiring.
The method used to connect earth conductors to earth should be in accordance with local regulations. Please consult your electricity distribution company. Suitable earthing media include:
a. Earthing electrode.
b. Underground water piping system.
c. Metallic sheathing of underground supply cable.
Other precautions
Normal laboratory and common sense precautions should be adhered to. Particular attention should be paid to the use and storage of flammable solvents. Do not leave uncovered containers of volatile organic solvents near a naked flame.
Do not store large quantities of solvent in the vicinity of the instrument. Ventilate the working area by using an efficient extraction system to remove burnt gases and toxic compounds that may be formed.
Periodically check all gas lines for leaks.
Hollow cathode lamps and flames (in particular the nitrous oxide-acetylene flame) emit ultraviolet radiation, so do not look at these sources without the aid of safety glasses or the flame shield.
Do not leave a flame unattended.
GBC AAS Pre-installation Guide 15
Site preparation
Site preparation
16 GBC AAS Pre-installation Guide
Location
The supplied instrument should be installed on a sturdy, level bench—deep enough to provide access to the rear gas and electrical connections during installation and service, and allow ventilation. Sufficient working area should be available in front of the instrument. Depending upon your instrument configuration, the bench should be long enough to accommodate the following:
All SavantAAs SavantAA Zeeman
SensAA XplorAA
AAS 1040 mm 1040 mm 900 mm 900 mm
Computer 500 mm 500 mm n/a 500 mm
Printer 400 mm 400 mm 500 mm 400 mm
GF5000 (option) 400 mm n/a 400 mm 400 mm
Total 2340 mm 1940 mm 1800 mm 2200 mm
Recommended bench
All SavantAA systems: 2340 mm x 700 mm
SensAA: 1800 mm x 700 mm
SensAA (external computer) or XplorAA: 2200 mm x 700 mm
See Figure 1, Figure 2, and Figure 3, page 17–18.
The overall dimensions of each instrument are:
All SavantAAs SensAA XplorAA
Depth 610 mm 600 mm 520 mm
Width 960 mm 850 mm 820 mm
Height 600 mm with chimney
560 mm 480 mm
NOTE: The extension chimney supplied as standard equipment with the SavantAA Σ (and as an option with SavantAA, SensAA and XplorAA) should not be confused with the fume extraction duct which is to be supplied by the customer. See Figure 4 to Figure 9.
Site preparation
GBC AAS Pre-installation Guide 17
SavantAA AASGF5000
Computerand
monitor
Keyboard
Printer
SDS720(on stand)
2340 mm
700 mm400
400 4001040 500
640
Figure 1: Recommended bench dimensions for full SavantAA system
SensAA
G 5000F
SDS720(on stand)
1800 mm
700 mm400
400 900
330
Keyboard
Printer
500
Figure 2: Recommended bench dimensions for full SensAA system
Site preparation
18 GBC AAS Pre-installation Guide
SensAA/XplorAA
G 5000F
SDS720(on stand)
2200 mm
700 mm400
400 900
330
Computerand
monitor
Keyboard
Printer
400500
Figure 3: Recommended bench dimensions for full SensAA (with external computer) or XplorAA system
Site preparation
GBC AAS Pre-installation Guide 19
Exhaust requirements
The requirements for fume extraction apply to all AA instruments. GBC recommends the use of an extraction system above the burner assembly, to vent the products of combustion to the outside of the building. An exhaust fan capacity of at least 6 m3/min is needed, with a damper control to regulate efficient exhaust without causing severe draught.
A fume extraction system (including a damper control and a stainless steel hood) is available from GBC (Part No. 99-0012-00 (220/240 V, 50 Hz), 99-0012-01 (110 V, 60 Hz), or 99-0400-00 (220 V, 60 Hz)). Please direct any enquiries to your GBC representative.
Fit the fume extraction hood directly above the sample compartment as shown in the following diagrams (Figure 4 to Figure 9), allowing approximately 50 mm clearance between the hood and the extension chimney (if fitted). Note that an extension chimney is essential for nitrous oxide-acetylene burners.
Figure 4: Extraction fan detail Figure 5: Ventilation duct detail
Site preparation
20 GBC AAS Pre-installation Guide
Extenstion Chimney SavantAA
650 mmMin
50 mm Min
1800 mmMin
StainlessSteel Hood
Flow Control
Ducting
Suction Fan
Figure 6: Fume extraction system for SavantAA
SavantAA Zeeman
PAL4000
680 mm Min
50 mm Min
1800 mm Min
Stainless Steel Hood
Flow Control
Ducting
Suction Fan
Figure 7: Fume extraction system for SavantAA Zeeman
Site preparation
GBC AAS Pre-installation Guide 21
Suction Fan
Flexible Ducting
Flow Control
Stainless Steel Hood
Extension Chimney
SensAA
1800 mmMin
520 mmMin
50 mm Min
Figure 8: Fume extraction system for SensAA
Figure 9: Fume extraction system for XplorAA
Site preparation
22 GBC AAS Pre-installation Guide
Power requirements
Each AAS operates from a single phase AC mains power supply.
Voltage: 110, 120, 220 or 240 volts.
Frequency: 50 or 60 Hz.
Power consumption: 3.6 Kw maximum (SavantAA Zeeman) 450 watts maximum (SavantAA) 300 watts maximum (SensAA) 300 watts maximum (XplorAA)
Instruments are factory-set to suit your local supply.
Sufficient power outlets should be provided for the AAS and any accessories. For the SavantAA Zeeman, refer to page 26. For the System 5000 graphite furnace, refer to page 32 for specific power requirements.
Voltage stabilizers are only required for regions where an unstable supply is expected. Note that Graphite Furnace systems should not be connected to voltage stabilizers because of the high peak-current requirement.
Gas requirements
The three commonly used gases in flame atomic absorption spectroscopy are acetylene, air and nitrous oxide. Use only instrument grade acetylene and nitrous oxide. For gas purity specifications, see page 39. It is preferable to locate the cylinders outside the laboratory and pipe the gases to the instrument.
Acceptable pressure and flow ranges
Pressure Flow
Minimum Maximum Minimum
Fuel Acetylene 55 kPa (8 psi) 96 kPa (14 psi) 12 L/min
Air 330 kPa (47 psi) 370 kPa (53 psi) 24 L/min Oxidant
Nitrous oxide 330 kPa (47 psi) 370 kPa (53 psi) 24 L/min
Gas lines should finish within 1.5 metres of the rear centre of the AAS. Terminate each line with ¼” male Swagelok® fittings. Three flexible gas lines 2 m long are supplied with the instrument for connecting to installed gas lines.
CAUTION: Do not use oxygen or oxygen-enriched air.
Acetylene cylinders must not be used at cylinder pressures below 500 kPa. Doing so could allow acetone to enter the fuel line and cause damage to the instrument.
ALL GAS LINES SHOULD BE LEAK TESTED BEFORE THE INSTRUMENT IS OPERATED.
Site preparation
GBC AAS Pre-installation Guide 23
Gas purifier unit
A gas purifier unit to purify both air and acetylene, coupled to an integrated flashback arrestor must be installed. The compressed air filtration unit removes oil, water and particulate matter from the air supply. The acetylene filtration unit removes liquid (acetone) and solid contaminants from the acetylene supply down to 1 ppm. A flashback arrestor prevents potential back-travel of the AA burner flame to the acetylene supply. A suitable filtration unit is the Balston™ 73–100 AA Gas Purifier (available from GBC, part no. 99-0284-00) recommended for preventative maintenance of gas control systems in the AAS.
Water requirements for analytical analysis
For flame analysis, use deionized water generated by a mixed-bed deionizing unit or equivalent.
For furnace analysis, use deionized water generated via a reverse-osmosis unit coupled to a mixed-bed deionizing unit or equivalent. Specifications should be:
Resistivity: 18 Mohm/cm
Silicates: <0.3 ppb
Heavy metals: <0.1 ppb
Inorganic total dissolved solids: <5 ppb
These are the maximum allowable limits, and typical deionizing systems should obtain much lower levels.
For both flame and furnace analyses, water used as a blank should have an absorbance <0.005.
Ambient requirements
Temperature range
The recommended operating temperature range is 10–35°C.
Humidity range
The recommended relative humidity limits are 8–80% (non-condensing).
Air quality
The operation of the instrument may be impaired by the presence of dust/corrosive vapours. Care should be taken to minimize their effects. This will normally entail a suitably ventilated or air-conditioned room, and good standards of laboratory practice in the handling and storage of chemicals. GBC accepts no responsibility for damage or lack of performance due to poor operating conditions.
Site preparation
24 GBC AAS Pre-installation Guide
Note that outlets from air-conditioning ducts should not be directly over or directed towards the instrument, as the airflow may affect results.
Clean air supply for XplorAA AAS (case purge only)
The XplorAA AAS uses positive air pressure inside the instrument to prevent the ingress of dust and/or corrosive vapours. A local supply of clean, dry compressed air should be provided (in addition to that required for flame analysis). This is connected to the regulator inlet of the XplorAA AAS using a standard ¼" BSP R/H thread connector.
Suitable supply pressures are in the range of 30–100 psi (200–700 kPa) at a volume of at least 60 L/min.
GBC AAS Pre-installation Guide 25
SavantAA Zeeman AAS
SavantAA Zeeman AAS
26 GBC AAS Pre-installation Guide
Power requirements
The SavantAA Zeeman is designed to operate from a single phase AC mains power supply:
Voltage: 220–240 VAC.
For areas with a lower supply voltage (e.g. 110 V), or poor mains regulation, see GBC AAS Service Note 057.
A minimum cable size of 2.5 mm2 is required. The circuit should be protected with a 30 A slow-blow device (HRC fuse or thermal circuit breaker, or a 40 A magnetic breaker).
Assuming an adequate power supply at the mains distribution board (i.e. rated voltage ±6% and 70 A transient capacity), wire size for minimal voltage drop between the mains distribution board and the power outlet to which the SavantAA Zeeman is to be connected can be selected from the table below:
Maximum cable length vs conductor size/minimum mains voltage
Minimum voltage measured at power board
220 V 230 V 240 V
2.5 mm2 6 m 12 m 18 m
Conductor 4 mm2 9 m 18 m 27 m
Size 6 mm2 14 m 28 m 42 m
10 mm2 25 m 50 m 75 m
WARNING: Under no circumstances should the same conductor be used for both earth and neutral connections.
Cooling water requirements
Cooling water at a flow rate of 1.2 L/min and a pressure of 200 kPa minimum (28 psi) is required to cool the furnace workhead. The SavantAA Zeeman contains a pressure sensor that will prevent operation of the furnace if the water pressure drops below the range of 0.75–1.2 L/min.
The temperature of the cooling water supply at the inlet should not exceed 45°C.
The SavantAA Zeeman will operate with up to 100 kPa back-pressure. The supply pressure should exceed the drain pressure by at least 150 kPa to achieve the required flow.
SavantAA Zeeman AAS
GBC AAS Pre-installation Guide 27
It is important that the water pressure be measured with a pressure gauge prior to delivery. If the water pressure is not within the specified range, the instrument cannot operate. Additional charges for commissioning could apply if inadequate water pressure causes delays. For sites with low water pressure, a recirculating water system should be installed. GBC can supply a refrigerated recirculating water system if required.
A suitable water system for cooling the graphite furnace workhead should have the following specification:
Cooling Capacity: Min 950 watts (817 Kcal/hr)
Temperature Range: +5°C to +35°C
Temperature Stability: ±1.0°C
Pumping Capacity: Min 1.5 L/min @ 410 kPa (60 psi)
GBC supplies and recommends a refrigerated cooling unit designed to meet the requirements of all GBC graphite furnace systems. Contact your local GBC representative for details.
SavantAA Zeeman AAS
28 GBC AAS Pre-installation Guide
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GBC AAS Pre-installation Guide 29
SDS720/PS720 sample delivery system
SDS720/PS720 sample delivery system
30 GBC AAS Pre-installation Guide
Site preparation
Position the SDS720 sampler and the PS720 preparation station on the workbench, preferably to the right of the AAS, or on the flame sampler trolley in front of the instrument. Refer to Figure 1, Figure 2 and Figure 3.
Dimensions: SDS720 530 mm x 530 mm x 530 mm (max) (WxDxH) * for clearance of 150 mm test tubes when probe is up.
PS720 80 mm x 380 mm x 350 mm (WxDxH)
Weight: SDS720 11.6 kg
PS720 4.5 kg
Power requirements
The SDS720 sampler and PS720 preparation station each operate from a single phase AC mains power supply.
Voltage: 110, 220 or 240 volts AC (Plug in auto-range mains voltage supply module to 24 VDC)
Frequency: 50 or 60 Hz
Power consumption: 80 watts maximum
Ordering information
Description Part Number
SDS720 Sample Delivery System 99-0582-00
PS720 Preparation Station 99-0597-00
GBC AAS Pre-installation Guide 31
System 5000 graphite furnace
System 5000 graphite furnace
32 GBC AAS Pre-installation Guide
Location
The preferred position for the GF5000 power supply is on the left or right side of the AAS towards the back of the bench. See Figure 1, Figure 2 and Figure 3.
Dimensions: 380 x 360 x 290 mm (WxDxH)
Weight: 35 kg
Power requirements
The System 5000 is designed to operate from a single phase AC mains power supply.
Voltage: 208, 220 or 240 volts
Frequency: 50 or 60 Hz
Rated Current: 15 amps
Surge Current: 40 amps
A minimum cable size of 2.5 mm2 is required. The circuit should be protected with a 30 A time delay device (HRC fuse or thermal circuit breaker, or a 40 A magnetic breaker). Assuming an adequate power supply at the mains distribution board (i.e. rated voltage ±6% and 70 A transient capacity), wire size for minimal voltage drop between the mains distribution board and the power outlet to which the GF5000 is to be connected can be selected from the table below:
Cable length Minimum conductor size
0–6 m 2.5 mm2
6–9 m 4 mm2
9–14 m 6 mm2
14–25 m 10 mm2
System 5000 graphite furnace
GBC AAS Pre-installation Guide 33
Gas requirements
Inert gas
This can be either high purity grade, oxygen-free nitrogen or high purity grade, oxygen-free argon at 70–200 kPa (10–30 psi). Insufficient pressure will inhibit operation. A flow rate of 3 L/min (approximately 4–5 units on the flow meter) is normally used. Inert gas is also required to pressurize the rinse reservoir of the PAL auto sampler. Its absence will prevent furnace operation. An inert gas outlet for this purpose is located on the rear of the GF5000 power supply.
Auxiliary gas
A second inert gas can be selected to flow in the furnace. This allows the cheaper nitrogen to be used during the long dry stage and the more expensive argon gas to be selected only during the critical ashing stages for elements where argon provides a better response.
Gas lines
Gas lines should finish within 1.5 metres of the rear centre of the GF5000. Terminate each line with ¼” male Swagelok® fittings. Two flexible gas lines 2 m long are supplied with the accessory for connecting to installed gas lines.
See gas purity specifications, page 39.
Cooling water requirements
Cooling water at a flow rate of 0.6 L/min and a pressure of 200 kPa minimum (28 psi) is required to cool the furnace workhead. The GF5000 contains an internal water-pressure regulator. If the water pressure falls below 100 kPa for more than one second, the System 5000 will shut down.
The water line supplied with the System 5000 is a 1.8 m length of 1/8” ID PVC tube. A cold water supply line terminating with a barbed hose connector to mate with this tubing is required.
The temperature of the cooling water supply at the inlet should not exceed 40°C.
There should be no back pressure in the drain for the GF5000.
It is important that the water pressure be measured, using a pressure gauge, prior to delivery. If the water pressure is not within the specified range, the instrument cannot operate. Additional charges for commissioning could apply if inadequate water pressure causes delays. For sites with low water pressure, a recirculating water system should be installed. GBC can supply a refrigerated recirculating water system if required.
System 5000 graphite furnace
34 GBC AAS Pre-installation Guide
A suitable water system for cooling the furnace workhead should have the following specification:
Cooling Capacity: Min 950 watts (817 Kcal/hr)
Temperature Range: +5°C to +35°C
Temperature Stability: ±1.0°C
Pumping Capacity: Min 1.5 L/min @ 410 kPa (60 psi)
GBC supplies and recommends a refrigerated cooling unit designed to meet the requirements of all GBC graphite furnace systems. Contact your local GBC representative for details.
GBC AAS Pre-installation Guide 35
HG3000 hydride generator
HG3000 hydride generator
36 GBC AAS Pre-installation Guide
Location
The HG3000 has mounting wings which allow it to be attached to the front of the burner compartment on SavantAA/SensAA/XplorAA instruments.
Dimensions
The overall dimensions of the HG3000 accessory are:
Width: 275 mm
Depth: 260 mm (excluding wings)
Height: 200 mm
Exhaust requirements
GBC recommends the use of a fume extraction system above the AAS burner to remove heat, fumes and the products of chemical reactions which occur during analysis. In particular, the use of concentrated HCl with the hydride generator requires the removal of corrosive vapour. Safe laboratory practices should be observed.
An exhaust fan is required with a capacity of at least 6 m3/min and a damper control to regulate efficient exhaust without causing severe draught.
A fume extraction system (including a damper control) is available from GBC (Part No. 99-0012-00 (220/240 V, 50 Hz), 99-0012-01 (110 V, 60 Hz), or 99-0400-00 (220 V, 60 Hz)). Refer to Figure 4 to Figure 9. Please direct any enquiries to your GBC representative.
Power requirements
The HG3000 operates from a single phase AC mains power supply.
Voltage: 110, 120, 220 or 240 volts
Frequency: 50 or 60 Hz
Power consumption: 23 watts continuous
The voltage and frequency settings are factory-set to suit your local supply.
HG3000 hydride generator
GBC AAS Pre-installation Guide 37
Gas requirements
Inert gas
An inert carrier gas is required for removing hydride vapour from the gas-liquid separator and conveying it to the absorption cell. Either high purity argon or nitrogen is suitable, at a regulated pressure of 225–455 kPa (30–60 psi). In some instances a slightly higher sensitivity (approximately 10%) may be achieved using argon rather than nitrogen.
Flow rate
During operation, the typical inert gas flow rate is 30 mL/min. For use with SnCl2, an additional gas flow of 120 mL/min is required.
Gas lines
Gas lines should finish within 1.5 metres of the rear centre of the AAS. Terminate each line with ¼” male Swagelok® fittings. One flexible gas line 2 m long is supplied with the accessory for connecting to the installed inert gas line. See Gas Purity Specifications, page 39.
Drain requirements
The gas-liquid separator has a drain line which carries the liquid away from the instrument. This drain line must not be restricted in any way. Drain to the same waste container used for flame AAS.
EHG3000 (99-0237-11)
The EHG3000 electric heater replaces the flame as an excitation source. It receives vapour input from the HG3000 Hydride Generator, and is powered by a separate free-standing power supply. There are no pre-installation requirements apart from the provision of a general purpose AC power outlet. Power requirement is 110–120/230–240 VAC, 120 VA. Dimensions of the power supply are 260 x 160 x 290 mm (WxHxD). It may be situated on top of the instrument.
MC3000 (99-0245-11)
The MC3000 Mercury Concentrator pre-concentrates mercury vapour from the HG3000 Hydride Generator by adsorption onto gold foil, then fast release by inductive heating. The vapour trap is powered by a separate free-standing power supply. The MC3000 requires an inert gas supply which is obtained from the HG3000 gas supply. A general purpose AC power outlet is also required. Power requirement is 110–120/230–240 VAC, 250 VA. Dimensions of the power supply are 260 x 160 x 290 mm (WxHxD). It may be situated on top of the instrument.
HG3000 hydride generator
38 GBC AAS Pre-installation Guide
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GBC AAS Pre-installation Guide 39
Gas purity specifications for AAS gases
Gas purity specifications for AAS gases
40 GBC AAS Pre-installation Guide
Normal compositions (flame and furnace gases)
Air (instrument grade)
Oxygen 21% Nitrogen 78% Argon 0.9% Carbon dioxide 300 ppm Methane < 5 ppm Moisture < 25 ppm at full cylinder pressure
Nitrous oxide (instrument grade)
Nitrous oxide > 99.5% Oxygen < 0.1% (liquid phase) Nitrogen < 0.4% (liquid phase) Moisture < 100 ppm
Nitrogen (high purity O.F.N.) (oxygen-free nitrogen)
Nitrogen 99.99% minimum Oxygen < 10 ppm Methane < 5 ppm Moisture at 15°C 12 ppm at full cylinder pressure on a rare-gas-free basis Carbon dioxide 0.1 ppm
Acetylene (instrument grade) (specially purified)
Acetylene 99.9% minimum on an acetone-free basis
Argon (high purity grade)
Argon 99.99% minimum Oxygen < 10 ppm Nitrogen < 50 ppm Carbon dioxide < 5 ppm Carbon monoxide < 1 ppm Hydrocarbon as CH < 1 ppm Hydrogen < 1 ppm Moisture < 12 ppm at full cylinder pressure
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