Rosemount 755A, Инструкция по эксплуатации

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I
NITIAL
S
TARTUP AND
C
ALIBRATION
3-8
April 2000 Rosemount Analytical 245364-U Model 755A Oxygen Analyzer
A. TYPICAL ZERO-BASED RANGES
0 to 1 Nitrogen 0.9% O
2
Balance N
2
0 to 10 Nitrogen 9% O
2
Balance N
2
0 to 100 Nitrogen 100% O
2
B. TYPICAL ZERO-SUPPRESSED RANGES
RANGE
% O2
RECOMMENDED STANDARD GAS
RECOMMENDED UPSCALE
STANDARD GAS
20 to 21 20.2%
±
0.2% O
2
Air (20.93% O
2
)
11 to 21 11.2%
±
0.2% O
2
Balance N
2
Air (20.93% O
2
)
99 to 100
High Purity O
2
with 0.8%
±
0.05% High
Purity N
2
High Purity O
2
90 to 100 91%
±
0.5% O
2
Balance N
2
High Purity O
2
3.3.3 C
ALIBRATION WITH
D
OWNSCALE AND
U
PSCALE
S
TANDARD
G
ASES
1. Set downscale calibration point as follows:
a. Set TEST switch (on analyzer door) to NORM.
b. Pass downscale standard gas through analyzer at suitable flow rate, preferably
250 cc/min. Allow gas to purge analyzer for minimum of 3 minutes.
Note:
The Zero and Span adjustments on the analyzer door are used only for the
calibration of the digital readout for 0 to 100% oxygen.
The suppressed recorder ranges may only be set up after the digital readout has
been calibrated. When setting up a suppressed recorder range, use only R41,
R104 (setpoint) and R88 (Span) for adjustments. DO NOT RE-ADJUST THE
ZERO AND SPAN CONTROLS ON THE ANALYZER DOOR.
c. Adjust ZERO Control so that the reading on the digital display 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. Refer to
Section 3.4.2). If proper reading is not obtained by an adjustment of the ZERO
Control, refer to Section 6, Routine Servicing.
2. Set upscale calibration point as follows:
a. Verify that front panel TEST switch is set to NORM.
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. S
TANDARD
G
ASES
R
ECOMMENDED FOR
C
ALIBRATION OF
V
ARIOUS
O
XYGEN
R
ANGES ON
A
NALOG
O
UTPUT