Rosemount 755, Инструкция по эксплуатации

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S
TARTUP
3-9
748183-H
Rosemount Analytical
November 1997
With air flowing SPAN control is adjusted so meter reads:
In two limiting cases, the general equation reduced to simpler forms.
1. If the upscale standard gas is 100% oxygen, the adjusted oxygen value for setting
the SPAN Control is the same as the true value, i.e., 100% oxygen .
2. If the downscale standard is an oxygen-free gas, the adjusted value for setting the
ZERO Control = BGGst - BGGs. (If the oxygen-free zero gas is more diamagnetic
than the background gas in the sample, this difference is negative. The meter scale
is not calibrated with negative values; however, a negative value may be set on the
recorder if provided with below-zero capability.)
21 (100 - 0.265) - 100 (-0.265)
100
= 21.209 % O
2