Heath Consultants Odorator Propane - Manual (Page 24)

Appendix C
chart actuals.
The reading of .23 is 60% of the difference in the chart higher reading from
the chart lower reading. The lower chart reading and actual will be used as
the base or reference.
.23 - .20
= .6 or 60%
.25 - .20
Therefore the actual value will be 60% of the difference in the chart higher
actual from the chart lower actual. Again, the lower value will be the base
or reference.
60% of (.22 - .19) = .6 x .03 = .018 which is rounded off to .02
Since the actual value base is .19, the actual value will be .19 + .02 = .21% gas.
Interpolation Example 2: DOWN Column
An ODORATOR reading of .23 is taken at 2700’. The calibration elevation is
5500’ so the elevation difference is 2700-5500 = -2800 which is rounded of to
-3000’. The difference is negative so the DOWN 3000 correction column will
be used.
A reading of .23 lies between chart readings of .20 and .25. This reading
also lies between actual values of .15 and .18 using the DOWN 3000 cor-
rection column.
The reading as a percentage between the adjacent chart readings can be
used to determine the actual value using the same percentage between
chart actuals.
The reading of .23 is 60% of the difference in the chart higher reading from
the chart lower reading. The lower chart reading and actual will be used as
the base or reference.
.23 - .20
= .6 or 60%
.25 - .20
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