Met One Instruments LVS-100, User Manual

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MicroVol-1100 User manual 1.6 Introduction
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1.1 Description
The MicroVol-1100 Particulate Sampler provides a flexible platform for sampling of
PM
10
, PM
2.5
or TSP particulate and for monitoring basic meteorological parameters.
Incorporating a pump, filter holder and flow control circuit, the sampler is
microprocessor based and features internal data logging of flow and meteorological
parameters.
The MicroVol-1100 constantly monitors the 'mass flow rate' of air passing through
the filter and pump. This mass flow is computed with the ambient pressure and
temperature sensor measurements to calculate the volumetric flow rate (e.g. 3L/min).
variation in pump vacuum is The pump is a linear diaphragm pump and the correct
flow rate is maintained by varying the amplitude of diaphragm movement, this
changes the vacuum created by the pump, more vacuum for more filter loading.
The MicroVol-1100 incorporates Active Volumetric flow control which mediates
pump speed and air velocity to guarantee a constant sampling flow-rate no matter the
filter loading of restrictions in place.
The MicroVol-1100 is designed to operate from a 12 VDC power supply. It can be
powered from a variety of different sources, including the AC mains power adaptor,
an optional battery pack, or solar panel and battery combination.
The MicroVol-1100 incorporates ambient temperature, pressure and humidity sensors,
which are used to automatically maintain a constant volumetric flow-rate of typically
3 litres per minute (l/min) through a 47mm-diameter circular filter.
The MicroVol-1100 includes the facility to monitor wind speed and direction, using
an optional external wind sensor. Wind speed and direction data are averaged and
stored in internal memory, and may be used as triggers for conditional sampling.
The MicroVol-1100 also incorporates a time clock and programmable timer enabling
multiple time based sampling programs to be configured.
The MicroVol-1100 internal data logger stores time based data averages at user
selectable intervals. The data includes date and time stamp, flow-rate, total sample
volume, average temperature, barometric pressure, and either wind speed and wind
direction or rain-fall information. Data values stored in the MicroVol may be
downloaded via the RS-232C Serial port.
The MicroVol-1100 is extremely quiet allowing it to be used at indoor sampling
locations to assess human exposure to particulate matter (PM), and is housed in a
weatherproof enclosure for outdoor sampling in a range of environments.
Some typical sampling applications include:
•
Sample collection at surface mines
•
Fence line sampling
•
Saturation sampling to determine gradients in PM concentration
•
Indoor air quality studies for health and safety
•
Locations where mains power is unavailable
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