Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 15)

<1. Overview>
1-1
IM 11M12A01-02E 8th Edition : Jan.13,2012-00
1. Overview
The EXAxt ZR Separate type Zircon Oxygen Analyzer is used to monitor and control the oxygen
concentration in combustion gases, in boilers and industrial furnaces, for wide application
in industries which consume considerable energy — such as steel, electric power, oil and
petrochemical, ceramics, paper and pulp, food, or textiles, as well as incinerators and medium/
small boilers. It can help conserve energy in these industries.
The EXAxt ZR also contributes to preservation of the earth’s environment in preventing global
warming and air pollution by controlling complete combustion to reduce CO
2
, SOx and NOx.
The ZR22G Separate type Detector uses a high-reliability Zirconia sensor, and its heater
assembly can be replaced on site. The detector is mounted, for example, on the wall of a flue and
can measure the gases directly.
For use in combustion gases at temperatures up to 1400 °C, choose the general use 0.15 m
long detector, which is combined with the ZO21P, the high temperature probe protector. The
converter is equipped with an LCD touch screen which has various setting displays, a calibration
display, oxygen concentration trend display, with easier operation and improvement of display
functions. The converter is equipped with various standard functions such as measurement and
calculation as well as maintenance functions including self-test. Analyzer calibration can also
be fully automated — and the ZR40H, an automatic calibration unit, is available. Choose the
detector version which best suits your needs so that an optimal combustion control system can
be obtained.
Some examples of typical system configurations are illustrated below:
1.1 < EXAxt ZR > System Configuration
The system configuration should be determined by the conditions; e.g. whether calibration is
to be automated, and whether flammable gas is present and requires safety precautions. The
system configuration can be classified into three basic patterns as follows:
1.1.1 System 1
This is the simplest system consisting of a detector and a converter. This system can be
implemented for monitoring oxygen concentration in the combustion gases of a package boiler.
No piping is required for the reference gas (air) which is fed in at the installation site. The handy
the ZO21S standard gas unit is used for calibration.
Zero gas from this unit and span gas (air) is sent to the detector through a tube which is
connected during calibration.
EXA ZR402G
ZR22G Separate type
Zirconia Oxygen Analyzer, Detector
ZR402G Converter
Stop valve
Calibration gas
ZO21S Standard gas unit
~
100 to
240 V AC
F1-1E.ai
Contact input
Analog output, contact output
(Digital output HART)
Signal
(6-core shield cable)
Heater(2-core)
~
Figure1.1