TSI Instruments 3082, Operation And Service Manual

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6-22 Electrostatic Classifier Model 3082 and SMPS Spectrometer Model 3938
4. The particle concentration should drop to a negligible level when
compared to the concentration to be measured.
To perform a DMA zero test, an SMPS spectrometer scan must be
completed. To perform a DMA test, follow these instructions:
1. Install a DMA and connect the classifier to the CPC.
2. Connect a computer running the Aerosol Instrument Manager software
to the classifier and open Aerosol Instrument Manager software.
3. Set up a scan for 180s at the sheath flow rate and aerosol flow rate
that will be used in your application. A sheath-to-aerosol flow ratio of
10:1 is preferred for most applications (such as 15 L/min sheath flow,
1.5 L/min aerosol flow).
4. Set up to run one scan.
5. Begin the scan without a HEPA filter installed on the inlet of the
classifier to verify appropriate response of SMPS spectrometer to room
air. You should see counts and a graph of the particle size distribution
representative of your sampling environment. Once particles are
observed, you can either end the scan or let the scan complete.
6. Remove the high efficiency HEPA filter from the Accessory Kit. Using a
length of clear tubing (not provided), connect the filter to the CPC inlet.