Emerson Rosemount X-STREAM O2 Transmitter, Инструкция по эксплуатации

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Hazardous Area
X-STREAM O
2
Transmitter
1-4
Instruction Manual
IM-106-910C, Rev. 1.0
November 2009
The sensor cell will read the O
2
concentration as a percentage of the total
volume of flue gases including water vapor. Therefore, it may be considered
an analysis on a "wet" basis. In comparison with older methods such as the
portable apparatus, which provides an analysis on a "dry" gas basis, the "wet"
analysis will, in general, indicate a lower percentage of oxygen. The
difference will be proportional to the water content of the sampled gas stream.
The transmitter electronics controls probe temperature and provides an iso-
lated 4-20 mA output that is proportional to the measured oxygen concentra-
tion. The probe heater can accept voltages of 100-240 VAC ±10% and 50/60
Hz. Therefore, no setup procedures for power are required. The oxygen sens-
ing cell is maintained at a constant temperature by modulating the duty cycle
of the probe heater portion of the electronics. The electronics accepts millivolt
signals generated by the sensing cell and the thermocouple produces the out-
puts to be used by the users computer or data acquisition system. The output
is an isolated 4-20 mA linearized current.
System Features
1. The cell output voltage and sensitivity increase as the oxygen
concentration decreases.
2. HART communication is standard; to use the HART capability you must
have either:
a. 375 Field Communicator.
b. Asset Management Solutions (AMS) software for the PC.
3. An optional Xi Enhanced Interface allows continuous O
2
display and full
interface capability.
4. Field replaceable cell, heater, thermocouple, and diffusion element.
5. The Hazardous Area X-STREAM is constructed of rugged 316L or 304
stainless steel for all wetted parts.
6. The heater is adaptable for line voltages from 100-240 VAC ±10%;
therefore, no configuration of heater voltage is necessary.
System Configurations
Integral Transmitter Electronics, HART Communications
Hazardous Area X-STREAM O
2
probes are available in lengths of 18", 3', and
6'. The blue electronics housing contains a signal conditioning electronics to
control the cell heater, and to condition the raw cell signal into a linear 4-20
mA signal, with HART digital communications. This arrangement has no dis-
play or keypad, and depends on a HART 375 communicator or AMS for con-
figuring the electronics, calibrating the probe, displaying O
2
information, and
diagnosing probe problems. This Hazardous Area X-STREAM configuration
is represented in Figure 1-2.