Page-6
Instruction 0023-9125
ODOROMETER
The instrument has two ranges, obtained by using a lightweight glass
and a heavier metal
fl
oat, both in the same metering tube. Take readings
on the glass
fl
oat when both are within the range of measurement; take
readings on the metal
fl
oat when the glass
fl
oat reaches the top of the tube.
Useful ranges are approximately 0.04 to 0.4% for the glass
fl
oat, and 0.2
to 1.1% for the metal
fl
oat.
When taking readings, observe the FLOWMETER graduation corresponding
to the bottom of the ball
fl
oat. Find the gas concentration corresponding to
this reading by looking at the calibration chart on the inside of the front
cover. This chart has been drawn to give the percent gas concentration over
the useful ranges for natural gas with a speci
fi
c gravity of 0.620 relative
to air. Concentrations of gases of other densities may be read using the
correction factors shown on the graph below the calibration chart.
The
FLOWMETER
tube and
fl
oats must be kept clean to prevent
sticking of the
fl
oats in the tube. To disassemble, press the sides of the
plastic cover and pull out. Remove the spring lock clip at the top of tube,
lift the tube connector and pull tube out, by lifting from the bottom con-
nectors. Tube and
fl
oats can be washed in alcohol, trichloroethylene or
other solvent.
When the odor (mercaptan) in gas has been detected, observe the reading
indicated by the FLOWMETER
fl
oat. Depending on the range required,
use either the upper glass
fl
oat (colored) for values 0.04 to 0.4% or lower
metal
fl
oat (silver) for values 0.2 to 1.2%.
EXAMPLE: FLOWMETER (silver
fl
oat) indicates 7; use second curve and
observe that percent gas indicated by the chart is 1.1% (%
GAS IN ODOROMETER EFFLUENT). If speci
fi
c gravity of
gas under test is 0.620, the correct percentage of gas is as
noted on the curve (1.1%). If speci
fi
c gravity differs, use the
CORRECTION CHART below.
EXAMPLE: Speci
fi
c gravity of gas under test is 0.55, the correction factor
noted on the chart is 1.06. The correct gas concentration is
obtained by multiplying the following:
1.1% x 1.06 = 1.166% (Gas in ODOROMETER Ef
fl
uent).
6.
RANGE OF
MEASUREMENT
7. MAINTENANCE
8.
HOW TO USE THE
ODOROMETER GAS
CALIBRATION
CHART
