PORTABLE AETHALOMETER AE42Online monitors
PORTABLE AETHALOMETER AE42
The ‘Portable’ Model AE-42 Series Aethalometer uses the same aerosol collection, analysis and data systems as the ‘full-size’ 19-inch rack chassis models AE21 and AE31, but is constructed in a smaller chassis and equipped with an internal battery which permits independent mobile (or portable) operation: or operation from an off-grid 12-volt power source such as a vehicle or solar PV array.
- Complete, self-contained chassis
- Dimensions: 19″ Wide, 11″ High, 12″ Deep
- Weight not to exceed 40 Pounds
- Filtration and Analysis Chamber to provides continuous filtration with optical transmission analysis to measure elemental carbon
- Automatically advancing quartz fiber filter tape
- Internal sample aspiration pump
- Air mass flow rate control with closed-loop feedback
- AC charger; cables for external 12-volt operation
- Sample inlet tubing
- Sample inlet fittings
- Roll of filter tape
- Floppy disk drive 3.5″
- Box of 3.5″disks
- <0.1 micrograms/meter-cubed sensitivity
- One (1) digital output
- One (1) analog output
- Internal rechargeable 12V battery (approximately 3 hour run time). Power consumption approximately 25 watts.
POWER SUPPLY ADAPTER
- 100~240 VAC 50/60 Hz Power Adapter supplied by Magee Scientific.
- May be operated from 12 V external power source.
- 0 ~ 40 °C operating, non-condensing.
- Approximately 15 minutes required from power-up to valid
SAMPLE STREAM DRYERDrying the aerosol sample stream is highly recommended to provide accurate measurement data and to protect the equipment from water condensation.
In hot, humid locations, the water vapor content of the ambient sample air may be very large. This can lead to inaccuracies in the BC measurement – but, more seriously, there is the possibility of water condensation inside the instrument which can lead to permanent damage. This issue is solved by the use of our Sample Stream Dryer.
The interaction of water with aerosol species changes their physical properties. Consequently, the World Meteorological Organization has recommended that all aerosol measurements should be performed under conditions where the Relative Humidity is 40% or lower (WMO/GAW 2003; Wiedensohler, 2014).
Many stations in hot, humid locations have air-conditioned interiors. If the indoor air-conditioning temperature Ta is comparable to or lower than the dewpoint (condensation temperature) Td of the outside ambient air, water will condense in the tubing and inside the instrument. This will not only completely in-validate the data, but it can also cause permanent damage to the instrument.
The Magee Scientific Sample Stream Dryer removes water vapor from the inlet flow by means of a semi-permeable Nafion membrane. This membrane selectively absorbs molecules of water vapor from the air-stream and passes them to a space on the other side of the membrane, maintained at a low absolute pressure by means of a vacuum pump.
The Magee Scientific Sample Stream Dryer can reduce the dew point temperature by up to 14 degrees Celsius at a flow rate of 5 LPM. The equipment is self-contained, automatic, and includes a display screen which shows the input and output hygrometric properties.
The Magee Scientific Sample Stream Dryer can be used to remove water vapor from the inlet stream to any aerosol instrument, not just an Aethalometer.
FILTER TAPEThe Model AE42Aethalometer collects its samples on a proprietary filter tape made of quartz fibers supported on a mechanical backing for transport in the instrument. When the spot reaches a pre-set loading density, the tape is advanced to create a new spot. Each roll of tape is 10 m. in length and will last from a few weeks to a few months, depending on the average concentration of BC in the sampled atmosphere and the operational flow-rate that is chosen.
SIZE-SELECTIVE INLETSAmbient atmospheres include suspended particles of large aerodynamic size such as pollen, dust, etc. These particles are not strongly optically absorbing and therefore do not interfere with the Aethalometer® analysis: however, after lengthy use a deposit of dust in the internal optics will degrade performance. To exclude large particles, and to provide analysis of a known respirable size fraction, we recommend use of size-selective inlets designed to exclude particles of aerodynamic size greater than a specified cut point at a specified sample air flow rate. We offer the ‘Sharp-Cut Cyclones’ designed by BGI (USA) and now manufactured by Mesa Labs (USA). These inlets are usually attached directly to the sample inlet tube at the point of entry, but may also be installed in-line closer to the Aethalometer..
BGI model SCC-1.828. Provides a cut point of 2.5µm at a sample flow rate of 5 LPM.
BGI model SCC-1.197. Provides a cut point of 2.5µm at a sample flow rate of 2 LPM, or 1µm at a sample flow rate of 5 LPM.
BGI model SCC-0.732. Provides a cut point of 1µm at a sample flow rate of 2 LPM.
BGI ‘Mini-PM’ Inlet Kit
The BGI ‘Mini-PM’ Inlet Kit offers impaction jet inserts to provide size selective capabilities of TSP, PM-4, PM-2.5, and PM-1, when operated at a flow rate of 5 LPM.