Method of Operation

The Qbit LCT-14 Particulate Matter Meter (PM) is an instrument based on the measurement of “Laser Scattering” or the measurement of light scattered by the particulate present in the air sample introduced into an optical interaction cell. This type of measurement allows obtaining a real-time value, i.e. a continuous measurement of the particulate content in the air. The LCT-14 instrument shares the technical characteristics of the LCT-12 fixed station, but is made in a case and battery powered. In this way it lends itself to the temporary monitoring of particular sites such as construction sites or workplaces at risk. It can be integrated with panel power and can be configured to send data to remote servers.

Operating Specifications

The Tablet control unit is powered by the instrument and therefore its battery is kept charged. In case of a black-out, the Tablet remains on for about 4-5 hours and restarts measurements as soon as the instrument is powered from the mains again.

Resolution and Accuracy of Measurement Signals:

1. As indicated at the beginning of this data sheet, the PM measurement resolution and accuracy data are relative to the optical signal produced by the particulate sample. The similar specifications on the mass value of particulate matter are derived from a calibration process that is sensitive to the type of sample tested (carbon dust, such as those typically found in winter due to heating systems result in a higher conversion coefficient than silica dust more typical of summer measurements). The accuracy of the mass data, at a specific site and in a specific time period, must therefore be evaluated by comparison over an interval of several hours with a gravimetric measuring system (Primary Method).
   
2. The accuracy of the measurement is greater the greater the measurement interval. For measurements longer than 10 seconds, accuracy can reach levels better than 1 part in 1000.
3. The standard range set at the Factory corresponds to a concentration of 1500 μg/m3 at Full Scale. Which produces for what is indicated in (2) a measurement sensitivity better than 2 μg/m3 For measurements on intervals of 10 seconds or more.
4. The temperature measurement is taken at the air intake of the instrument. It is therefore indicative of the measurement temperature in the optical cell. It may differ by a few degrees from the “external ambient temperature” due to heat dissipated by the instrument itself.