Heath Consultants ODORATOR 2 - Manual (Page 5)

1
Introduction
The ODORATOR 2 is a handheld, portable, electronic GNSS based audit system used to
evaluate and record the odor
levels within a utility’s gas stream with respect to actual test
locations. Natural gas (methane) and propane are two common gases typically odorized and
distributed for consumption.
Sample gas to be tested enters the ODORATOR 2 through the quick connect fitting at the gas
supply inlet port. Internally, the sample gas passes through an internal five micron filter to the
input of a low pressure regulator. It then passes from the output of the low pressure regulator
to the flow metering valve. This valve, located on the top panel of the ODORATOR 2, is
controlled by the user. After passing through the valve (when partially opened), the gas enters
a mass flow sensor. This is the heart of the ODORATOR 2. The mass flow sensor responds
to gas flow within the range of the flow metering valve. The signal from the mass flow sensor
is then converted to a digital signal, processed and fed to a liquid crystal display (LCD) for the
user
’s use. Metered gas from the mass flow sensor then passes to the mixing chamber where
it is combined with fresh air drawn in by a blower. The user then sniffs the gas / air mixture at
the exhaust port as part of the test. If no odor is detected in the exhaust mix the flow metering
valve is incrementally opened and the exhaust port sniffed until odor is readily detectable at
which time the user presses the READ switch to automatically record the corrected percent
gas in air by volume, GNSS location (GPS and/or GLONASS), test time, test date and various
instrument parameters. While driving to the various test points in the distribution system the
ODORATOR 2 also automatically records the GNSS location, date, time and various
instrument parameters to be able to show the actual breadcrumb trail used. The electronics
and the speed of the blower are calibrated so that the concentration of the gas / air sample at
the exhaust port agrees with the LCD reading at 20% of the Lower Explosive Level (LEL). For
methane or natural gas the LEL is typically 5.0% and for propane the LEL is typically 2.2%. All
readings are automatically corrected for atmospheric pressure and temperature via an
embedded microcontroller and associated sensors. Depending on how far the flow metering
valve is opened, the concentration of gas in air at the exhaust port will be anywhere from zero
up to approximately 2% for methane. An alarm and the display warn the user of instrument
problems or high reading values.
INTRODUCTION
The ODORATOR 2 continuously monitors its health and operational status. Typical
operational checks include but are not limited to: blower speed, battery state-of-charge, GNSS,
memory card, communications buss, power supplies and calibration interval.
Included but not required for odor level testing is OdorSeer PC software for managing the
recorded data, mapping, report generation and instrument configuration. Connectivity
interfaces include USB 2.0 and Bluetooth. Refer to the OdorSeer manual for details.
A replaceable, rechargeable Li Ion battery pack is used to power the ODORATOR 2. An
external power supply is used to re-charge the battery pack. The ODORATOR 2 is designed
and intended to be used in accordance with the GPTC Guide For Gas Transmission And
Distribution Piping Systems, (49 CFR) 192.625 Subpart L, dated 10-1-13, the American
Society For Testing And Materials Standard D 6273
– 08 and NFPA 58. Supply gas must be
natural gas (methane) or propane and of high quality. Blended or mixed gases as sometimes
found during peak shaving cannot be tested using the ODORATOR 2.