Rosemount 755, Инструкция по эксплуатации

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M
ODEL
755 O
XYGEN
A
NALYZER
4-2
748183-H
Rosemount Analytical December 1997
EXAMPLE (S.I. Units)
Pst = 101 kPa
Pan = 98.2 kPa
Indicated % O
2
= 40%
True % O
2
= 101/98.2 x 40% = 41.1% O
2
4.3 CALIBRATION FREQUENCY
The appropriate calibration interval will depend on the accuracy required in the
particular application, and is best determined by keeping a calibration log. If the
analyzer exhaust port is vented directly to the atmosphere, the greatest source of error
is normally the variation in barometric pressure. If desired, effects of barometric
pressure variation can be minimized by calibrating immediately before taking readings,
for example, at the beginning of each shift.