YOKOGAWA ZR22S, User Manual

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<1. Overview>
1-1
IM 11M13A01-02E
1. Overview
The EXAxtZR Separate type Explosion-proof Zirconia 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 EXAxtZR 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.
ZR22S Separate type Explosion-proof 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-purpose 0.15
m long detector, which is combined with 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 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 system is for monitoring and controlling oxygen concentration in the combustion gases of
a large-size boiler or heating furnace. Clean (dry) air (21%O
2
) is used as the reference gas and
the span gas for calibration. Zero gas is fed in from a cylinder during calibration. The gas flow is
controlled by the ZA8F flow setting unit (for manual valve operation).
ZA8F
Flow Setting Unit
ZR22S Separate type Explosion-proof
ZR402G Converter
Reference gas
Calibration gas
Stop valve
or
Check valve
Needle
valve
Flowmeter
Instrument air
Air Set
Pressure
reducing
valve
Zero gas
cylinder
F01-1E.ai
Span gas (*)
* Calibration gas unit same as for zero gas.
Zirconia Oxygen Analyzer, Detector
Calibration gas
unit case
EXA ZR402G
Non-hazardous Area
Hazardous Area
~ 100 to 240 V AC
Contact input
Analog output,
contact output
Digital output
(HART)
*1
Figure 1.1 System configuration 1