Rosemount 755, Инструкция по эксплуатации

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M
ODEL
755 O
XYGEN
A
NALYZER
3-4
748183-H Rosemount Analytical
November 1997
A. ZERO BASED RANGES
RANGE
% O
2
RECOMMENDED DOWNSCALE
STANDARD GAS
RECOMMENDED UPSCALE
STANDARD GAS
0 to 1 Nitrogen 0.9% O
2
, balance N
2
0 to 2.5 Nitrogen 2.3% O
2
, balance N
2
0 to 5 Nitrogen 4.5% O
2
, balance N
2
0 to 10 Nitrogen 9% O
2
, balance N
2
0 to 25 Nitrogen Air (20.93% O
2
)
0 to 50 Nitrogen 0.45% O
2
, balance N
2
0 to 100 Nitrogen 100% O
2
B. ZERO SUPPRESSED RANGES
RANGE
% O
2
RECOMMENDED DOWNSCALE
STANDARD GAS
RECOMMENDED UPSCALE
STANDARD GAS
90 to 100 91% 0.5% O
2
, balance N
2
High-purity O
2
80 to 100 82% 1% O
2
, balance N
2
100% O
2
60 to 100 62% 1% O
2
, balance N
2
100% O
2
50 to 100 52% 1% O
2
, balance N
2
100% O
2
Note
Each standard gas used should have a composition within the specified
limits, and should have a certified analysis provided by the supplier.
T
ABLE
3-2. C
ALIBRATION
R
ANGE FOR
V
ARIOUS
O
PERATING
R
ANGES
3.2.1 C
ALIBRATION WITH
D
OWNSCALE AND
U
PSCALE
S
TANDARD
G
ASES
Set downscale calibration point as follows:
a. Set % RANGE Switch in a position appropriate to the selected standard
gases. The switch may be set for the range to be used during sample analysis.
For maximum precision however, it should be set for the range of highest
sensitivity, i.e., most narrow span.
b. Pass downscale standard gas through analyzer at suitable flow rate preferably
250 cc/min. Allow gas to purge analyzer for minimum of three minutes.
c. Adjust ZERO Control so that reading on meter or recorder is appropriate to the
downscale standard gas. (The required reading may be the actual oxygen
content of the downscale standard gas, or may be an adjusted value,
depending on the relative magnetic susceptibilities involved, and the range
and span used, see Section 3.3.2.) If proper reading is unobtainable by an
adjustment of the ZERO Control, refer to Section 7, Service and Maintenance.
d. If previous reading was obtained on a recorder, set Meter Adjustment R38,
see Figure 3-1, so that meter reading agrees with recorder setting.
2. Set upscale calibration point as follows:
a. Set % RANGE Switch in position appropriate to the selected upscale standard