Sampling - YOKOGAWA ZX8D User Manual

4.3

Sampling

WARNING
• This unit is not explosion-proof type. Do not use it in a place with explosive gases to prevent
explosion, fire or other serious accidents.
• When combustible gases are contained in measuring gas, check the gas composition and
instrument specifications before use, or else the best performance may not be obtained or
there may be a danger of explosion.
Sample gas conditions
n
• Dust included in sample gas should be completely eliminated with a filter. Use a filter
capable of eliminating dust particles of 0.3 μm at the final stage.
• The dew point of sample gas must be lower than the ambient temperature to avoid
condensation of drain inside the analyzer. If water vapor is included in sample gas, then use
a dehumidifier to lower the dew point to about 0°C.
• If SO mist is included in sample gas, then use a mist filter, cooler or the like to exclude it.
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Other types of mist should also be excluded.
• Strongly corrosive gases like Cl
life of the instrument. Harmful components such as Si vapor, alkaline metals, P, Pb and SO
at high concentrations (1000ppm or more) will also shorten its service life.
• Sample gas temperature should range from 0 to 50°C. Do not introduce a high temperature
gas directly into the instrument.
• Combustible gases such as H
reaction and produce a measuring error.
Sample gas flow rate
n
Set the sample gas flow rate at 0.5±0.25 L/min.
Preparation of standard gas
n
Prepare standard gas for zero point and span calibration.
Zero gas (span gas in rule of measuring)
Span gas (zero gas in rule of measuring)
, F and HCl included in sample gas will shorten the service
2 2
and CO included in sample gas will consume O
2
Air
1 to 2% O /N
2 2
via a
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IM 11G00E01-01EN 6th Edition : May. 21, 2018-00
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