Rosemount 890, Инструкция по эксплуатации

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U
NPACKING AND
I
NSTALLATION
748460-A
2-5
Rosemount Analytical
January 2000
2.6 CALIBRATION GAS REQUIREMENTS
Analyzer calibration consists of setting a zero point and one or more upscale points.
All applications require a zero standard gas to set the zero point on the display or
recorder chart. If the factory Calibration and Data Sheet (included with the drawings at
the end of the manual) specifies a background gas, use this as the zero gas. If a
background gas is not specified, use dry nitrogen for the zero gas. Ideally, span gas
should be between 75 % and 100 % of the fullscale span.
2.7 SAMPLE HANDLING SYSTEM
Many different sample handling systems are available, either assembled completely or
as loose components. The type used depends on the requirements of the particular
application and the preferences of the individual user. Typically, the sample handling
system incorporates such components as pumps and valves to permit selection of
sample, zero standard and upscale standard gas; needle valve in sample-inlet line for
flow adjustment; flowmeter for flow measurement and/or indication of flow stoppage;
and filter(s) to remove particulate matter.
2.8 LEAK TEST PROCEDURE
This analyzer is capable of analyzing sample gases which may be flammable. If
used for analysis of such gases the instrument must be protected by a
continuous dilution purge system in accordance with Standard ANSI/NFPA 496-
1989 (Chapter 8).
If explosive gases are introduced into the analyzer, the sample containment
system must be leak checked upon installation and before initial startup, during
routine maintenance and any time the integrity of the sample containment
system is broken, to ensure that the system is in leak proof condition.
Internal leaks resulting from failure to observe these precautions could result in
an explosion causing death, personal injury or property damage.
The following test is designed for sample pressure up to 10 psig (69 kPa).
1. Supply air or inert gas such as nitrogen at 10 psig (69 kPa) to analyzer via a flow
indicator with a range of 0 to 250 cc/min and set flow rate at 125 cc/min to the
sample inlet.
2. Seal off sample outlet with a cap.
3. Use a suitable test liquid such as SNOOP* (PN 837801) to detect leaks. Cover all
fittings, seals or possible leak sources.
WARNING: POSSIBLE EXPLOSION HAZARD