TSI Instruments SIZER 3321, User Manual

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A-4 Model 3321 Aerodynamic Particle Sizer

Spectrometer
C a u t i o n
The electronic circuits within this instrument are susceptible to electro-
static discharge (ESD) damage. Use ESD precautions to avoid
damage.
 Use only a table top with a grounded conducting surface
 Wear a grounded, static-discharging wrist strap
C a u t i o n
Any time that you remove a portion of the optics assembly for cleaning,
there is a chance that you can adversely affect the alignment of the
system and therefore the calibration. It is a good idea to check the
calibration of the instrument after any procedure involving the optics. Do
this by generating a know size of aerosol, ie. 1 µm polystyrene latex
(PSL) and making sure that the aerosol is sized correctly by the
instrument and software.
1.
Switch the power off using the switch on the back of the cabinet and
unplug the power cord from the APS
™
spectrometer.
2.
Remove the knurled retaining ring from the outer inlet nozzle.
3.
Loosen the six screws on both sides of the cabinet (two turns is
sufficient) and remove the cover straight upward.
4.
Remove the outer inlet nozzle by gripping it and lifting straight up.
5.
Grip the inner nozzle and lift straight up.
6.
Remove the two screws securing the digital printed circuit board.
7.
Tilt the printed circuit board upward and remove the large ribbon
cable connector from the center front of the board.
8.
Tilt the printed circuit board all the way back so that the pumps are
visible and the board rests against the top edge of the back of the
instrument.
9.
Label the two tubes coming from the nozzle mount and going to the
pumps (a fine-tip permanent marker works well). Label the top tube
“top” and the bottom tube “bottom”.
10.
Grip each tube and remove it from the nipple fitting attached to the
nozzle mount.
11.
Loosen the knurled retaining ring at the base of the nozzle mount.
12.
Lift the nozzle mount away from the optics block taking care not to
scratch or damage the delicate outer nozzle. Make sure that the O-
ring under the nozzle mount stays with the optics block.
Note : The outer nozzle is very delicate. Take great care in cleaning or
blowing compressed air through the nozzle.
13.
Blow clean, compressed air backwards through the outer nozzle to
remove any debris.