System 2 - YOKOGAWA ZR402G User Manual

Stop valve
Figure1.1
NOTE
• As this system uses ambient air for the reference gas, measuring accuracy will be affected
by the installation location.
• A stop valve should be connected to the calibration gas inlet of the equipment. The valve
should be fully closed unless calibration is in progress.
1.1.2

System 2

This system is for monitoring and controlling oxygen concentration in the combustion gases of
a large-size boiler or heating furnace. Instrument air (clean and dry air of oxygen concentration
21%) is used as the reference gas and the span gas for calibration. Zero gas is fed from a
cylinder during calibration.
In case of humidity analyzer, this system is for accurate monitoring and controlling humidity when
the installation environment is polluted with gases other than the air.
Instrument air (clean and dry air of oxygen concentration 21%) is used for the reference gas and
the span gas for calibration.
The gas flow is controlled by the ZA8F flow setting unit (for manual valve operation).
Stop valve
or
Check valve
Figure1.2
ZR202G Integrated type
Zirconia Oxygen/Humidity Analyzer
~
100 to 240 V AC
Contact input
Analog output, contact output
Digital output (HART)
Calibration gas
ZO21S Standard gas unit
Example of System 1
ZR202G Integrated type
Zirconia Oxygen/Humidity Analyzer
~
100 to 240 V AC
Contact input
Analog output, contact output
Digital output (HART)
Flowmeter
Reference gas
Calibration gas
ZA8F flow setting unit
Example of System 2
100/110/115
~
200/220/240 V AC
Needle
valve
Air Set
Instrument air
Span gas(Same as Zero gas calibration)
Calibration
gas pressure
regulator
Calibration gas unit case
<1. Overview>
F1.1E.ai
Zero gas cylinder
F1.2E.ai
IM 11M12A01-04E 11th Edition : Jul. 19, 2017-00
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