ISOKINETIC COUPLER FOR THE
MODEL 3302A AEROSOL DILUTER
AND MODEL 3340
LASER AEROSOL SPECTROMETER
USER’S GUIDE
Description
The Model 3302A Aerosol Diluter is used for many applications where
aerosol dilution is required. The dilution ratios and the calibrated flow
rate through the diluter are determined at 5 L/min. The Model 3340
Laser Aerosol Spectrometer (LAS) runs at a lower sampler flow rate. An
isokinetic coupler between the 3340 LAS and the 3302A Aerosol Diluter
is described here (Part Number 1140001) which will enable the use of
the 3302A Aerosol Diluter with the 3340 Laser Aerosol Spectrometer.
A sampling probe designed to allow low-flow isokinetic sampling to the
Laser Aerosol Spectrometer is inserted in a modified, Swagelok fitting
which couples to the 3302A outlet. Critical orifices protected by a filter
and an external pump (not supplied) are used to pull an auxiliary flow
which will maintain a flow of 5 L/min through 3302A, while maintaining
the necessary sample flow for the 3340 LAS.
3302A Aerosol Diluter
3340 Laser Aerosol Spectrometer
Operation
1. Install the 1:100 capillary into the 3302A Aerosol Diluter.
2. Connect the 1140001 Isokinetic Coupler to the
bottom
outlet port of the 3302A.
3. Place the assembly on top of the 3340 using a spacer or stand (not included). The tube from the 3340
inlet to the Isokinetic Coupler should be straight.
4. Connect and switch on the external pump (e.g. TSI model 3032).
5. Set the LAS sampling flow to 0.10 L/min.
6. Adjust the pressure across the capillary (
p
aerosol
) in the 3302A according to the calibration sheet
supplied with the instrument.
