U
NPACKING AND
I
NSTALLATION
245364-U Rosemount Analytical April 2000
2-9
Model 755A Oxygen Analyzer
CAUTION: OPERATING LIMITS
during passage of the sample through the analyzer. This precaution ensures against
cooling of the sample and possible condensation of moisture. Such condensation
should be avoided as it may damage the detector.
2.6.2. S
AMPLE
P
RESSURE
R
EQUIREMENTS
: G
ENERAL
Operating pressure limits are the following: maximum, 10 psig (69 kPa gauge
pressure); minimum, -1.9 psig (-13.1 kPa).
Operation outside the specified limits may damage the detector and will void the
warranty.
Oxygen readout is automatically corrected for atmospheric pressure variations within
±
3% of the target value, which may be set anywhere within the range of -2.7 to 3.3
psig
±
3 psig (-18.6 to 22.8 kPa
±
21 kPa).
The basic rule for pressure of sample and standard gases supplied to the inlet is to
calibrate the analyzer at the same pressure that will be used during subsequent
operation and to maintain this pressure during operation. The arrangement required
to obtain appropriate pressure control will depend on the application. Refer to special
instructions included in Section 2.6.3, Normal Operation at Positive Gauge Pressures;
or Section 2.6.4, Operation at Negative Gauge Pressures.
F
IGURE
2-7. C
ONNECTION OF
T
YPICAL
G
AS
S
ELECTOR
P
ANEL TO
M
ODEL
755A
O
XYGEN
A
NALYZER
Downscale
Standard
Gas
Upscale
Standard
Gas
Sample In
Needle
Valves
Flowmeter
Two Micron
Filter
Model 755A
Oxygen Analyzer
To Vent
