Metek 920, Руководство оператора с основными требованиями по охране здоровья и безопасности

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5-4 | Model 920 Multi-Gas Analyzer
Frequency Task
Monthly
Check Analyzer Response Time
Note: Do this task in conjunction with the monthly task “Check the PMT
Signals” above.
Manually Zero the analyzer. After the Zero is complete, determine the
sample response time by switching the analyzer from Continuous
Backpurge mode to Continuous Sample mode. Observe the RUN
mode normal display and record the time it takes the analyzer to display
the first reading after the switch. Typically, a good response time is in
the range of 30 seconds. A response time that is slower than normal
may suggest plugging problems in the analyzer’s sample system.
Refer to “Manually Zeroing the Analyzer” and “Setting the Sample
Gas Flow Rate and Sample Response Time” in Chapter 3. See also
“Preventing, Detecting, and Locating a Plug in the Sample System” in
this chapter.
Monthly
Pressure Gauge
Check the Aspirator Pressure gauge.
Aspirator air pressure should be set in the range of 7–35 KPAG (1–5
PSIG). See “Setting the Sample Gas Flow Rate and Sample Response
Time” in Chapter 3.
Pressure Transducer Air pressure is set at a nominal 105 KPAG (15
PSIG).
CAUTION:
To avoid damaging the pressure transducer, do not set the
pressure higher than 105 KPAG (15 PSIG).
Monthly Temperature Zones
Check and record the temperatures of all temperature zones and ensure
they are all within 5 % of their Set Point values.
Every 3 Months Sample Conditioning Unit (SCU), Optional
If your analyzer uses a SCU, change the filter elements in the SCU
(Probe). If the gaskets are damaged, replace them at the same time.
Clean the parts that make up the filter assemblies.
Replace the
gaskets at 6-month intervals, minimum.
Depending on sample stream contamination levels (i.e., sample
response time is continually decreasing), replacing filters and cleaning
the SCU more frequently may be necessary. This may be evident
if response time is longer than normal, or if a good zero cannot be
achieved.
If your system uses a SCU (or other sample gas extraction unit) from a
manufacturer other than AMETEK, refer to its manual for maintenance
requirements.
Every 6 Months Sheltered Systems
If the analyzer is installed in a custom shelter, check the air filters for the
shelter purge and air conditioning systems, and replace if necessary.
Depending on the environmental conditions of the site, more frequent
filter replacement may be necessary.
Every 6 Months Sample/Vent Lines
Inspect the Sample Line and Vent Line (if used) for sags, sharp
bends, or damage to the outer skin. If necessary, take appropriate
safety precautions and replace the lines. Perform a leak check on all
associated fittings after replacing any line(s).