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P a r t i c l e I n s t r u m e n t s Model 3936 SMPS (Scanning Mobility Particle Sizer) Instruction Manual P/N 1933796, Revision G August 2002...
SMPS System Overview Unpacking the SMPS Model 3936 SMPS System (Scanning Mobility Particle Sizer) Setting Up SMPS Hardware Instruction Manual Operating SMPS Hardware Maintaining and Troubleshooting the SMPS System Service Appendixes and Index...
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M a n u a l H i s t o r y The following is a history of the Model 3936 SMPS Scanning Mobility Particle Sizer Instruction Manual, P/N 1933796. Revision Date First printing March 1999 Final April 1999...
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1. GRANT OF LICENSE. TSI grants to you the right to use one copy of the Software License enclosed TSI software program (the “SOFTWARE”), on a single computer. You may (effective March 1999) not network the SOFTWARE or otherwise use it on more than one computer or computer terminal at the same time.
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S a f e t y This section gives instructions to promote safe and proper operation of the Model 3936 Scanning Mobility Particle Sizer (SMPS system), samples of warnings found in this manual, and information on labels attached to system instruments. L a s e r S a f e t y The Model 3936 Scanning Mobility Particle Sizer and Model 3010, 3022/3022A, and 3025/3025A Condensation Particle Counters...
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Using the CPC with hazardous gases may cause injury to personnel and damage to equipment. viii Model 3936 SMPS (Scanning Mobility Particle Sizer)
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R a d i a t i o n S a f e t y The Model 3080 Electrostatic Classifier contains a Model 3077 Aerosol Neutralizer with a Krypton-85 source. Under normal circumstances, you will not come into contact with hazardous radiation.
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Model 3936 SMPS (Scanning Mobility Particle Sizer)
C o n t e n t s Manual History................iv Warranty..................v Safety ..................vii Laser Safety ................vii Electrical Safety ..............vii Chemical Safety ..............viii Radiation Safety ..............ix Labels ..................ix About This Manual ..............xv Purpose.................xv Related Product Literature ............xv Reusing and Recycling ............xv Submitting Comments ............
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Impaction Theory and Operation .........B-2 Electrostatic Classifier ............B-4 Charging Theory ..............B-7 Particle Mobility Theory.............B-11 Condensation Particle Counter..........B-15 CPC Theory ..............B-16 Particle Counting............B-18 Operating at Higher Concentrations .......B-19 The Data Measurement Process ........B-21 References ................B-23 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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C Calculation of the Geometric Mean and Geometric Standard Deviation for Number, Surface, and Volume Distributions ..........C-1 I n d e x Index ..................I-1 F i g u r e s 1-1 SMPS System Shown with a Model 3085 Nano DMA and Model 3025A CPC............
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Midpoint Mobilities, Midpoint Particle Diameters, and Fraction of Total Particle Concentration that Carries +1, +2, +3, +4, +5, and +6 Elementary Charges as a Function of Mobility ..........B-9 B-2 Coefficients for Equation B-2..........B-10 B-3 Coincidence Levels ............B-20 Model 3936 SMPS (Scanning Mobility Particle Sizer)
A b o u t T h i s M a n u a l P u r p o s e This is an installation and operations manual for the Model 3936 Scanning Mobility Particle Sizer (SMPS system). R e l a t e d P r o d u c t L i t e r a t u r e The following TSI product manuals may be of use as references to the SMPS system.
If the comment sheet has already been used, please mail, fax or email your comments on another sheet of paper to: TSI Incorporated 500 Cardigan Road Shoreview, MN 55126 Fax: (651) 490-3824 Email: particle@tsi.com Model 3936 SMPS (Scanning Mobility Particle Sizer)
C H A P T E R 1 S M P S S y s t e m O v e r v i e w This chapter contains an introduction to the Model 3936 Scanning Mobility Particle Sizer (SMPS system) and a brief explanation of how the system operates.
Detecting small changes in rapidly changing aerosol systems H o w t h e S y s t e m O p e r a t e s The Model 3936 SMPS system measures the number size distribution of particles using an electrical mobility detection technique.
S y s t e m Use the information in this chapter to unpack the various components of the Model 3936 SMPS system. P a c k i n g L i s t s Table 2-1 gives the main components of the system. Please consult individual product manuals, with the exceptions of the Interface Pack, for packing lists.
If anything is missing or appears to be damaged, contact your TSI representative, or contact TSI at 1-800-874-2811 (USA) or 001- (651) 490-2811. Chapter 6, “Service,” gives instructions for returning the SMPS system to TSI Incorporated. Model 3936 SMPS (Scanning Mobility Particle Sizer)
C H A P T E R 3 S e t t i n g U p S M P S H a r d w a r e This chapter gives information you need to set up the Model 3936 Scanning Mobility Particle Sizer (SMPS) hardware: Cabling connections A sequence to apply power to the different instruments...
SMPS system. If you apply power to the instruments at this stage in the setup process, the CPC and Electrostatic Classifier will be ready to operate when you select and set flowrates in Chapter 4. Model 3936 SMPS (Scanning Mobility Particle Sizer)
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1. Before you apply power, set the analog output in any CPC to HOST. If you do not set the analog output to HOST, there may be communications problems between the computer and the CPC. Typically, CPC analog outputs are set to HOST at TSI. For the Model 3010 CPC, set the analog output to HOST using DIP switches 6, 7, and 8 on the back panel of the instrument.
Nano DMA and a Model 3010 CPC: 1. Connect the CPC vacuum connection (¼-inch tube connection on back panel) to a vacuum source or pump (see the Model 3010 CPC manual for details). Model 3936 SMPS (Scanning Mobility Particle Sizer)
Figure 3-1 Model 3010 CPC with Nano DMA 2. Locate the ¼-inch outer diameter flexible tubing (3001903) from the Classifier accessory kit and cut a length to 10 inch [25 cm]. 3. Locate the Fitting adapter assembly (1035992) from the SMPS ⁄...
-inch end over the inlet of the CPC. 5. Locate the Flow equalizer assembly (1035989) from the SMPS accessory kit and attach the straight portion of the tee to the fitting adapter on the CPC. Model 3936 SMPS (Scanning Mobility Particle Sizer)
6. Position the CPC so that the flexible tubing connects from the DMA monodisperse aerosol outlet to the tee. Connecting the Model 3022 CPC Use the procedures in this subsection to connect a Model 3022 CPC to the Classifier in underpressure or in overpressure mode. Model 3022 with Nano DMA Refer to Figure 3-3 and the following instructions to connect the plumbing between a Model 3080 Classifier with Model 3085...
DMA and a Model 3022 CPC: Figure 3-4 Model 3022 CPC with Long DMA 1. Locate the ¼-inch outer diameter flexible tubing (3001903) from the Classifier accessory kit and cut a length to 10 inches [25 cm]. Model 3936 SMPS (Scanning Mobility Particle Sizer)
2. Locate the Flow equalizer assembly (1035989) from the SMPS accessory kit and attach the straight portion of the tee to the inlet on the front of the CPC. 3. Position the CPC so that the flexible tubing connects from the DMA monodisperse aerosol outlet to the tee.
Model 3025 with Long DMA Refer to Figure 3-5 and the following instructions to connect the plumbing between a Model 3080 Classifier with Model 3081 Long DMA and a Model 3025 CPC: 3-10 Model 3936 SMPS (Scanning Mobility Particle Sizer)
Figure 3-6 Model 3025 CPC with Long DMA 1. Locate the ¼-inch outer diameter flexible tubing (3001903) from the Classifier accessory kit and cut a length to 10 inches [25 cm]. 2. Locate the Fitting adapter assembly (1035992) from the SMPS ⁄...
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3-12 Model 3936 SMPS (Scanning Mobility Particle Sizer)
C H A P T E R 4 O p e r a t i n g S M P S H a r d w a r e After you have set up the SMPS system plumbing in Chapter 3, use the information in this chapter to do the following: Select flowrates Set flowrates...
3010 CPC, and can be toggled between 0.3 lpm or 1.5 lpm in the case of the 3022 or 3025 family of CPCs. Other flows require the use of the flow equalizer assembly (filter and valve) to provide filtered makeup air to the CPCs. Model 3936 SMPS (Scanning Mobility Particle Sizer)
Polydisperse Control Knob Display Aerosol Neutralizer Impactor Inlet Polydisperse Aerosol In ∆ Exhaust ∆ (Optional) Orifice Bypass Filter Bypass Pump Filter Filter Excess Monodisperse Sheath Pump Heat Aerosol Out Temp Absolute Exchanger Sheath Sensor Pressure Flowmeter Figure 4-3 Schematic Flow Diagram of the Classifier with NDMA The Nano DMA has the option of using a bypass flow to draw additional flow up to the inlet slit of the DMA (to reduce transport time and, therefore, diffusion losses for small particles.
When the impactor cut is not at or below the upper measured particle size limit, care must be taken interpreting the data. This is particularly true if Model 3936 SMPS (Scanning Mobility Particle Sizer)
there are a large number of particles with a size near or above the upper measurement limit. Particles larger than the upper size limit may carry multiple charges and will cause over counting in the upper size channels. You can use three different orifices with the impactor: 0.0457 cm, 0.0508 cm, and 0.071 cm diameter.
Before operating the SMPS system, check the system to ensure the system is leak-tight and the flows are laminar. All flowrates must be set to proper values before checking the system (see “Setting Flowrates” in this chapter). Model 3936 SMPS (Scanning Mobility Particle Sizer)
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1. On the Classifier, the voltage control should be set to “Panel Ctrl” (lower left pane on display—see Figure 4-1) to allow the DMA voltage to be controlled from the front panel, and the DMA Voltage control (upper left pane on display) must be set to 0 volts (off).
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Model 3936 SMPS (Scanning Mobility Particle Sizer)
C H A P T E R 5 M a i n t a i n i n g a n d T r o u b l e s h o o t i n g t h e S M P S S y s t e m This chapter gives maintenance recommendations, as well as a section on troubleshooting the Model 3936 Scanning Mobility...
Use the information in this section to check the SMPS system plumbing for leaks. Use the Classifier Manual procedures to check for leaks in the Model 3080 Classifier, and use the CPC manual procedures to check for leaks in your CPC. Model 3936 SMPS (Scanning Mobility Particle Sizer)
System Plumbing Use the following procedure to check the SMPS system plumbing. 1. Disconnect the CPC from the Classifier and disconnect the flow equalizer assembly from the CPC. 2. Open the valve in the flow equalizer assembly and plug any two of the three ports.
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Model 3936 SMPS (Scanning Mobility Particle Sizer)
C H A P T E R 6 S e r v i c e This chapter gives directions for contacting people at TSI Incorporated for technical information and directions for returning the Model 3936 Scanning Mobility Particle Sizer (SMPS system) for service.
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Model 3936 SMPS (Scanning Mobility Particle Sizer)
A P P E N D I X A S p e c i f i c a t i o n s Table A-1 gives specifications for the Scanning Mobility Particle Sizer (SMPS system). These specifications are subject to change. Table A-1 SMPS Specifications Concentration range ..
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Model 3936 SMPS Scanning Mobility Particle Sizer...
A P P E N D I X B T h e o r y o f O p e r a t i o n This appendix describes the theory of operation and working equations for the individual instruments that make up the Scanning Mobility Particle Sizer (SMPS system).
Classifier (see Figure B-1). The aerosol first enters an impactor, which removes particles above a known particle size by inertial impaction. The aerosol flow is accelerated through a nozzle directed at a flat plate, as shown in Figure B-2. Model 3936 SMPS (Scanning Mobility Particle Sizer)
Figure B-1 Classifier Shown with Impactor Installed on Inlet Impaction Nozzle or Stream Lines Impaction Plate Figure B-2 Cross-Sectional View of an Inertial Impactor [Hinds, 1982] The impaction plate deflects the flow to form a 90° bend in the streamlines. Particles with sufficient inertia are unable to follow the streamlines and impact on the plate.
E l e c t r o s t a t i c C l a s s i f i e r The purpose of the Electrostatic Classifier is to extract a known size fraction of submicrometer particles from the incoming polydisperse aerosol. Model 3936 SMPS (Scanning Mobility Particle Sizer)
In the Electrostatic Classifier, the aerosol enters a Kr-85 Bipolar Charger (or neutralizer), which exposes the aerosol particles to high concentrations of bipolar ions. The particles and ions undergo frequent collisions due to the random thermal motion of the ions. The particles quickly reach a state of equilibrium, in which the particles carry a bipolar charge distribution.
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) through a small slit located at the bottom of the collector rod. These particles are transferred to a particle sensor to determine the particle concentration. The remaining particles are removed from the Classifier via the excess air flow (q Model 3936 SMPS (Scanning Mobility Particle Sizer)
Polydisperse Control Knob Display Aerosol Neutralizer Impactor Inlet Polydisperse Aerosol In ∆ Exhaust ∆ (Optional) Orifice Bypass Filter Bypass Pump Filter Filter Excess Monodisperse Sheath Pump Heat Aerosol Out Temp Absolute Exchanger Sheath Sensor Pressure Flowmeter Figure B-4 Flow Schematic for the Electrostatic Classifier with NDMA C h a r g i n g T h e o r y The particle charge distribution used in the data reduction for the SMPS is based on a theoretical model developed by Wiedensohler...
Table B-1 lists the fractions of particles in air that carry +1, +2, +3, +4, +5, and +6 charge units. N=Charge Figure B-5 Bipolar Particle Charge Distribution in Air [Wiedensohler and Fissan, 1988] Model 3936 SMPS (Scanning Mobility Particle Sizer)
Table B-1 Midpoint Mobilities, Midpoint Particle Diameters, and Fraction of Total Particle Concentration that Carries +1, +2, +3, +4, +5, and +6 Elementary Charges as a Function of Mobility Fraction of Total Particle Mobility Particle Concentration That Carries This Midpoint Diameter Number (1-6) of Positive Charges /v-s...
P a r t i c l e M o b i l i t y T h e o r y As mentioned previously, only particles with a narrow range of electrical mobilities are extracted by the DMA to be measured by a particle sensor.
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= 1.905 cm (for NDMA) = inner radius of the annular space = 0.937 cm (for LDMA) = 0.937 cm (for NDMA) V = average voltage on the inner collector rod (volts) B-12 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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L = length between exit slit and polydisperse aerosol inlet ∗ = 44.369 cm (for LDMA = 4.987 cm (for NDMA) b = gap spacing between plates Equations B-4 and B-5 can be combined to give an equation that relates the particle diameter to collector rod voltage, number of charges on the particle, Classifier flowrate, and geometry for the LDMA or NDMA: (for LDMA &...
< 4 lpm 1000 0.001 0.01 Particle Diameter, Dp, µm Figure B-6 Collector Rod Voltage as a Function of Particle Diameter for Normal Operating Conditions of the LDMA [Agarwal and Sem, 1978] B-14 Model 3936 SMPS (Scanning Mobility Particle Sizer)
C o n d e n s a t i o n P a r t i c l e C o u n t e r There are five models of CPCs: Models 3010, 3022, 3022A, 3025, and 3025A. All CPCs operate on the same principle and are capable of interfacing with the Electrostatic Classifier to form an SMPS system (SMPS).
, at a given temperature. The condensing vapor, in this case, is butyl alcohol. The relationship between the saturation ratio and the minimal particle size is controlled by the Kelvin equation: σ ρ Equation B-10 B-16 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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where: σ = the surface tension M = molecular weight ρ = the density of the liquid = the Kelvin diameter. = universal gas constant = absolute temperature The Kelvin diameter is the droplet diameter that will neither grow nor evaporate at the saturation ratio p/p .
10,000 particles/cm . This mode is termed the single-particle count mode, and it is important to understand the errors associated with this mode to obtain accurate results from the SMPS system. B-18 Model 3936 SMPS (Scanning Mobility Particle Sizer)
At concentrations below 10,000 particles/cm , the pulse of light scattered by each particle is counted separately and the concentration is computed from the frequency of pulses. In this mode (the count mode), there is error due to particle coincidence. Error is most important at the upper end of the count mode where the concentration range is near 10,000 particles/cm .
At concentrations above 10,000, the Model 3010 CPC display flashes in the concentration mode (PT/CM ). If this occurs, the number of particles shown on the display could be substantially lower than the actual concentration. B-20 Model 3936 SMPS (Scanning Mobility Particle Sizer)
T h e D a t a M e a s u r e m e n t P r o c e s s ® Aerosol Instrument Manager Software for SMPS and the microcomputer tie the Electrostatic Classifier, the impactor, and the Condensation Particle Counter (CPC) together to form the SMPS system.
Calculation of statistics is also done at the selected resolution with its associated channel averaging. Transfer Function Electrical Mobility ∆ Figure B-10 Transfer Function of the Electrostatic Classifier [Knutson and Whitby, 1975] B-22 Model 3936 SMPS (Scanning Mobility Particle Sizer)
R e f e r e n c e s Adachi, M., K. Okuyama and Y. Kousaka [1985] “Electrical Neutralization of Charged Aerosol Particles by Bipolar Ions.” Journal of Chemical Engineering, Japan, 16:229. Agarwal J.K., and G.J. Sem [1978] “Generating Submicron Monodisperse Aerosols for Instrument Calibrations.”...
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Proceedings31st Annual Technical Meeting, Institute of Environmental Sciences, Las Vegas, NV, pp. 25-28, 30 Apr – 2 May. Plomp A. et al. [1982] Proceedings of the 10th Annual Gesellschaft für Aerosolforschung Conference Bologna, Italy. B-24 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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Pui, D.Y.H., and B.Y.H. Liu [1979] Technical paper: “Aerosol Generation and Calibration of Instruments.” Mechanical Engr. Dept. Univ of MN, May/June. Rohmann, H. [1923] Z. Phys. 18:188. Schürmann, G. [1986] “Measurement Techniques for HEPA-Filters in the Range of 0.03 µm–1 µm.” Proceedings of the 4th World Filtration Congress, Ostead, Belgium, April, pp.
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B-26 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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A P P E N D I X C C a l c u l a t i o n o f t h e G e o m e t r i c M e a n a n d G e o m e t r i c S t a n d a r d D e v i a t i o n f o r N u m b e r , S u r f a c e , a n d V o l u m e D i s t r i b u t i o n s The information in this appendix can be used with the Aerosol...
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Model 3936 SMPS (Scanning Mobility Particle Sizer)
I n d e x Concentration accuracy, B-20 acknowledgments, iv equation, B-20 address, TSI, iii high, B-19 Aerosol Neutralizer. ( see also Model 3077) range, A-1 handling, vii Condensation Particle Counter (CPC) packing, vii cable (serial), 3-2 removing, 6-1 concentration, A-1 safety, vii efficiency curves, B-18 airflow, checking, 4-6...
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B-15 Interface Pack with Nano DMA, 3-7 packing list, 2-2 Model 3022A configuration mode, 3-3 electrical safety, v flow schematic, B-15 Kelvin diameter, B-17 laser safety, v manual, xiii theory of operation, B-15 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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Model 3025 Model 3936 (continued) configuration mode, 3-3 packing lists, 2-1 connecting to Classifier, 3-9 photograph, 1-1 electrical safety, v plumbing arrangement, 3-1 flow schematic, B-16 power sequence, 3-2 laser safety, v product description, 1-1 theory of operation, B-15 returning for service, 6-1 with Nano DMA, 3-9 setting up hardware, 3-1 with Long DMA, 3-10...
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5-1 high voltage, vi recommendations, 5-1 optical radiation, v schedule, 5-1 radiation, vii operating hardware, 4-1 warranty, iii operation, 1-2 packing lists, 2-1 Windows. ( see Microsoft Windows) plumbing arrangement, 3-1 Model 3936 SMPS (Scanning Mobility Particle Sizer)
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Please help us improve our manuals by completing and returning this questionnaire to the address listed in the “About This Manual” section. Feel free to attach a separate sheet of comments. Manual Title Model 3936 SMPS (Scanning Mobility Particle Sizer) P/N 1933796 Rev. G 1.
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