Thermo Scientific PRO902C, Инструкция по эксплуатации

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PRO902C MANUAL
T FS
Rev 6.0 August 16, 2007 3-2
The dilution probe conditioning assembly should be installed in a location that will allow
maintenance personnel access to the front of the enclosure. All maintenance can be
performed from the front of the unit.
3.2
Limitations at the probe site
The placement of the PRO902C dilution probe conditioning assembly is important to achieve
its maximum reliability.
3.2.1 Stack temperature extremes
The PRO902C probe barrel was supplied using hastelloy C-276, Teflon
®
lined hastelloy C-
276, or other suitable material specific to the application. The Teflon
®
lined hastelloy probe
barrel may be used at temperatures up to 190.5

C (375

F) and lengths up to six (6) feet long.
Use the shortest possible probe barrel length (less than six feet) for proper response times
and consistent sampling practice.
3.2.2 Ambient temperature extremes
The PRO902C dilution probe conditioning assembly may be operated at a maximum ambient
temperature of -20

C to 50

C (-4

F to 122

F). This upper temperature is selected to assure
proper operation of the electronic circuitry and solenoid valves contained in the enclosure.
Optimum operation of the sampling system will always be achieved if a sampling location is
selected with moderate temperatures.
3.2.3 Process pressure
The sampling system should not be installed in sampling locations that have pressures that
5 inches H
2
O (1.2kPa) or -10 inches H
2
O (-2.5kPa). Positive pressure ducts are a
special problem because process gases may escape into the area of maintenance personnel
when the filter body is opened for maintenance. Positive pressure stacks or ducts may be
easily sampled if a small portion of the stream is vented to atmosphere and the probe installed
to sample this atmospheric vent. The probe typically pulls between 50 and 300 cc/minute,
requiring only a small bypass flow.
3.3 General Installation
3.3.1 Dilution probe conditioning assembly
The dilution probe conditioning assembly is shipped in two separate containers. The
conditioning assembly is installed first and then the probe barrel is installed through the
back of the conditioning assembly into the stack. To install the dilution probe
conditioning assembly, perform the steps outlined in the following three sections.