TSI Instruments 3082, Operation And Service Manual

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Product Overview 1-5
Sheath Flow
Sheath flow is required for use with DMAs. The sheath flow controller
maintains a constant flow through the sheath flow loop. The loop consists
of a pump (blower), two HEPA filters, a heat exchanger, flowmeter, a
temperature sensor, a relative humidity (RH) sensor, and a pressure
sensor. The flow is monitored by the microprocessor and used to control
the pump based on the desired flow rate set on the display. The heat
exchanger removes heat produced by the pump. The temperature and
pressure sensors update particle mobility and size readings on the display.
Neutralizer
The neutralizer provides a known charge distribution on the aerosol
entering the DMA. The classifier can be operated with a Model 3077
Krypton-85 Neutralizer or a Model 3088 Advanced Aerosol Neutralizer
which uses soft x-rays. The Model 3077 is available in two versions:

Model 3077, 74 MBq, (2 mCi).

Model 3077A, 370 MBq, (10 mCi). Used for higher flow and higher
particle concentrations. In many countries, the Model 3077A can only
be operated with lead shielding in place.
The 3088 Neutralizer receives power from, and communicates directly
with, the classifier.
The neutralizers are shipped as separate modules. Detailed descriptions of
the neutralizers are contained in their respective manuals.