Metek 920, Operator'S Manual With Essential Health And Safety Requirements

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5-2 | Model 920 Multi-Gas Analyzer
Under normal operating conditions, lethal concentrations of H2S and
other toxic gases from the sample stream may be present within the
sample system. The sample system is defined as all components in the
analyzer system through which sample gas passes.
Before working on the sample system, manually Zero the analyzer,
isolate it (block it in) from the sample stream, and disconnect the
power. Follow this procedure prior to changing out any analyzer com-
ponents or replacing any parts (as part of regular preventive mainte-
nance), or when performing leak checks following the replacement of
instrument air or other adjustments to any of the connection points
in the analyzer’s sample system.
If this is not possible, a breathing
apparatus must be worn while servicing the sample system.
If handling the circuit boards, do not subject them to static discharge.
The ideal solution is a static-safe work area. Since such areas typically
are not available at analyzer installation sites, the use of a wrist strap
connected directly to a ground is recommended. If a wrist strap is
not available, you should at the very least touch the metal chassis to
ground yourself before handling the boards.
Preventive Maintenance
The “Analyzer Preventive Maintenance Schedule” lists general mainte-
nance to follow, to ensure continued and proper operation of the analyzer.
Preventing leaks in the sample system is critical to proper analyzer
operation. If sample gas migrates into the Reflector Block or Optical
Bench (uncommon) due to a leak in the Measuring Cell, the optics
will become damaged and most likely require replacement. Most
leaks are preventable with regular cleaning and replacement of the
Measuring Cell o-rings.
Leak check the analyzer’s sample system whenever it has been dis-
mantled for maintenance.
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CAUTION
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WARNING
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CAUTION