2-4
Model 3090/3090AK Engine Exhaust Particle Sizer
TM
Spectrometer
S e t t i n g U p t h e E n g i n e E x h a u s t P a r t i c l e
Sizer S p e c t r o m e t e r
The following provides information for setting up the Model 3090 Engine
Exhaust Particle Sizer (EEPS) spectrometer.
Instrument Placement
The instrument cabinet is designed to be cooled by room air drawn in
through a filter from the back of the cabinet and exhausted through the
sides and front of the cabinet.
The cabinet should be installed with at least 3-inch (50-mm) clearance
between the back panel and side panels and any other surface. The
cabinet should be set on a flat, solid surface that isolates the instrument
from outside vibration. Excessive vibration will produce artificial noise in
the measurement.
When positioning the instrument, also allow adequate space at the back for
access to the power switch and for the power cord.
Installing the Cyclone
The cyclone functions by removing large particles, preventing counting
errors, and keeping the instrument clean. The cyclone is always used, and
should only be removed when transporting or servicing the instrument. The
cyclone will remove large particles and fibers that can cause excessive
noise on one or more channels. Since cleaning the electrodes is a
relatively involved procedure, it is much better to prevent contamination
using the cyclone. The cyclone will be more effective in removing large
fibers if the inside surfaces are lightly coated with a light oil.
Install the cyclone on the aerosol inlet using the union fitting shown in
Figure 2-2. Make certain the components are tightly pushed together.
Tighten the nuts on the union fitting finger tight and then ½-turn with a
wrench (see Swagelok recommendations).
C a u t i o n
Be certain that the Cyclone is installed on the Aerosol Inlet in the
orientation shown in Figure 2-1 prior to making particle size
measurements. Make sure that the cyclone is cleaned regularly and that
it is removed and cleaned before shipping.
