TSI Incorporated 8587A, Руководство по эксплуатации и обслуживанию

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5-2 Model 8587A Laser Photometer
Filter Replacement Instructions
When replacing the filters, first unplug the Laser Photometer power cord.
Remove the four screws at the top of the instrument cabinet and loosen the
screws at the base. Remove the cover by pulling it up. The sheath and
purge filters are clearly visible. Use Figure 3-5 as a guide to identifying
filters. The exhaust filter is located at the base of the instrument.
W A R N I N G
To avoid electrical shock, the instrument must be unplugged prior to
performing filter replacement operations.
C a u t i o n
To avoid damaging or disconnect wiring, use great care when removing
and replacing filters.
The sheath filter uses barbed fittings to make the tubing attachments. To
remove the purge air filter, grasp the filter housing and turn counter-
clockwise until the filter separates from the valve. If the brass pipe nipple is
removed with the filter, rather than staying in the valve, separate it from the
filter and apply pipe compound and replace it in the valve. Discard the used
filter and select the new one. Apply a small amount of pipe compound to
the interior threads of the filter and replace it. The exhaust filter is found on
the bottom of the cabinet.
S e n s o r C o n t a m i n a t i o n
Over time the photometer optics and internal surfaces of the scattering
chamber may become contaminated with particles. The result will be an
increase in Zero voltage level. The Zero voltage is measured during the
PURGE mode of operation and is normally between 7

10
-6
and 3

10
-5
volts. Since this voltage is subtracted from signal measurements, a change
in this value is normally not important. If the detector zero is very high,
>8

10
-5
volts, accuracy will be lost.
Periodically check the reading during the purge mode operation. If the zero
voltage is approaching 8

10
-5
volts, the Laser Photometer may need to be
returned to the factory for service. This will depend somewhat on the
application requirements.