Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 17)

IM 11M12A01-05E 1-3
1. Overview
1.1.3 System 3
This system is also used where accurate monitoring and controlling of the humidity is
required. Instrument air (clean and dry air of oxygen concentration 21%) is used as the
reference gas and span gas for calibration. A calibration zero gas is supplied from a
cylinder. This system uses an automatic calibration unit to control the calibration gas
flow automatically.
~ 100 to 240 V AC Auto Calibration unit
ZR20H
Reference gas
Calibration gas
Contact input
Analog output, contact output
Digital output (HART)
Air Set
Instrument air
Calibration gas
unit case
Calibration gas pressure regulator
Zero gas cylinder
Model ZR202G Integrated type Zirconia
High Temperature Humdity Analyzer
with auto calibration (ZR202G-hhh-h-h-A-h-h-h-h-A)
F1.3E.EPS
Span gas
Note:
The installation temperature limits for an integrated unit range from -20 to 55 8C.
*2
*3
*1
*1 Shield cable:
Use shielded signal cables, and connect the shields to the FG terminal of the con-
verter.
*2 Select the desired probe from the Probe Configuration table on page 1-4.
*3 100% N
2
gas cannot be used as the zero gas. Use approx. 1 vol% O
2
gas (N
2
-based).
Figure 1.3