Description
- Detects ultrafine carbon aerosols in real-time
- Lightweight, compact and ruggedized construction
- Battery powered with onboard data storage
- Applications related to personal exposure in various environments (homes, workplace, automobiles, tunnels etc.)
- Companion product to the DC 2200CE — the DC 2200CE measures ALL particulate matter, the PAS 2200CE measures PAH (primarily on carbonaeous matter)
Measuring Principle
The PAS 2000 works on the following principles:
• Using an Excimer lamp the aerosol flow is exposed to UV radiation. The Excimer lamp offers a high intensity, narrowband source of UV radiation. The wavelength of the light is chosen such that only the carbon aerosols are ionized, while gas molecules and non-carbon aerosols remain neutral.
• The carbon aerosol particles emit electrons, which are subsequently removed when an electric field is applied.
• The remaining positively charged particles are collected on a filter inside an electrometer, where the charge is measured. The resulting electric current establishes a signal, which is proportional to the concentration of Elemental Carbon and/ or PAH.
Also by operating the Excimer lamp in a chopped mode, the PAS 2000 can eliminate the background signal, which is associated with freshly generated aerosols. The chopped mode also enables a dynamic zero to be generated automatically by the instrument.
Calibration
Source-specific calibration curves are available or can be generated where the monitor output is compared to an analytically determined EC and PAH concentration. A site-specific calibration curve can provide greater accuracy for the particle size, charge and compound-specific to the source. In addition to the site-specific curves, an approximate universal calibration curve can be used for screening and real-time trending applications.
Technical Specification
- Display: 16 characters with 2 lines LED
- Power: 115 volts AC / 60 Hz & 220 volts AC / 50 HzMax.
- Battery: 15 volts Lithium Metal Hydride
- Range : 0 to 4000 ng/m3 (conversion to particle-surface area is site-specific)
- Sensitivity: ~ 10 ng/m3 (actual calibration is site-specific)
- Lower Threshold: ~ 10 ng/m3
- Response time: < 10 seconds (adjustable)
- Digital Output: RS – 232 (for data download and program upload)
- Analog Output: 0 to 10 volts
- Sample gas: Built-in pump with flowrate controlled at 1 L/min
- Operating temp: 40 to 104 ºF (5 to 40ºC)
- Dimensions: Height x Width x Depth = 3in x 7in x 5in ( 68mm x 175mm x 124mm )
- Weight: 3 lb. ( 1.5 kg )
- Data Storage: 8000 data points (each data point consisting of : Time, Value )
- Data Download: User-friendly PC-compatible graphical software used for downloading the collected data. Flat ASCII file output can also be generated for further analysis (e.g. Microsoft Excel format)