Rosemount 890, Инструкция по эксплуатации

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I
NITIAL
S
TARTUP AND
C
ALIBRATION
748460-A
3-23
Rosemount Analytical
January 2000
the recorder and Current Output do not get updated until the calibration sequence is
completed.
The range selection [RANGE: 1Y 2Y 3Y] display allows the user to select the ranges
which will be automatically calibrated with span gas by using the
→
arrow to move the
cursor to the desired range and using the
↑
or
↓
key to select Y (yes) or N (no) for
each range. The zero for all three ranges will be calibrated at each interval regardless
of range(s) selected.
The initial delay [DELAY nnn HR] display allows the user to select the amount of time
until the first automatic calibration occurs. This is the initial delay until the automatic
cycle starts. At this time a zero and span calibration is made regardless of selection. If
a zero delay is selected there will be an automatic two minute delay.
The purge [PURGE: nnn MIN] display allows the user to select the amount of time for
the calibration gas to flow through the analyzer before the calibration starts for zero
and span or the amount of time for sample gas to flow through the analyzer before run
mode values are recorded when the sample and hold feature is selected. The analyzer
is calibrated during the final minute of purge time. During the remaining purge time the
signal is modified according to previous calibration data.
The repeat zero [RPT ZERO nnn HR] display allows the user to select the amount of
time between zero calibrations. This is the amount of time after the initial calibration
before the zero calibration is repeated without repeating the span calibration.
Note:
Each time an auto span calibration is made, a zero calibration is also made
regardless of selection.
During the auto zero/span sequence, the time constant is set to one second.
Upon completion of the calibration sequence, the time constant is reset to the
value chosen in Range Parameters. The keyboard is disabled during the auto
zero/span sequence.
In order to engage the Auto-Cal function with the Remote Range I/O, the
Auto-Cal function must be disabled by toggling AUTO-CAL to OFF in the
[AUTO-CAL:OFF] display.
The repeat span [RPT SPAN nnn HR] display allows the user to select the amount of
time between span calibrations. This is the amount of time after the initial span
calibration before this calibration is repeated.
The [DRIFT LIMIT: ON] display allows the user to determine the maximum amount of
span and zero drift allowable. The [ZR-DFT:
±
XX%] or [SP-DFT
±
XX%] display
allows the user to select the percentage of fullscale by which the analyzer is allowed
to drift from the reference span or zero calibration values. The maximum zero drift limit
is 10% fullscale and the maximum span drift is 15% fullscale.