MSA MultiGard 5000, Руководство пользователя

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12
3103-1001 Rev. 0
2.5 Plumbing
NOTE: This section specifically applies to the standard MultiGard 5000 system look-ahead bypass
flow scheme. Refer to Section 1 if your system employs a custom flow scheme.
Remove all shipping plugs from sample point inlets, exhausts and drain.
Sample point supply lines should be 0.250" OD, 0.175" ID, with a maximum sample line length of
500 ft. As a general rule, sample lines should be kept as short as possible to reduce sample transport
time.
Sample point tube entries should be placed in areas that provide the unit with the best representative
gas sample to be detected. In large areas where multiple sample point entries are located, air flow
patterns must be taken into considered. Ventilation smoke tubes (P.N. 458480) are useful in
determining air flow patterns in ambient sampling areas.
The samples must be adequately filtered and free of any liquid contamination before entering the
system. End of line particulate filters must be installed at all sample point tube entries (see Flow
Diagram). The sample point tube entries must be unobstructed to allow the gas sample to flow freely
to the system. Use only materials that are compatible with the gases in the sample flow system to
ensure an accurate gas sample is delivered to the system. Ensure that all tubing bends are wide
enough to prevent kinking or restriction in sample flow.
When connecting fittings to the sample point inlets, exhaust, and/or drain ports, be sure to not over-
tighten the fittings. Overtightening the fittings may cause damage to the sample point manifold.
Exhaust and drain gas flow should be properly vented to a safe area. When exhausting outdoors,
make sure that rain or water sources cannot enter the exhaust lines. Do not combine any
sensor/analyzer exhausts or drain lines. Increase exhaust line diameter by a minimum of 1/8" per 20
ft. of exhaust line. Do not back pressure the exhaust lines by restricting flow. Exhaust lines should
also be checked for obstructions. Also, do not connect exhaust lines to a vacuum source.
2.5.1 Sample Line Leak Checking
WARNING
Leak-check all sample lines at start up and regularly thereafter.
Leaking sample lines will cause sample dilution and lead to
erroneous lower than actual readings.
Failure to leak-check the
sample lines may result in a hazardous condition.