The Palas® condensation particle counter ENVI-CPC 200 is a CPC for environmental ambient air monitoring. Model 200 is appropriate for high concentrations and offers single particle counting up to 2,000,000 particles/cm3. It can be used for ambient air monitoring without a dilution system.

The ENVI-CPC 200 can be equipped with an isothermal Nafion® aerosol dryer that has no consumables and can be used for months without maintenance. The humidity of the aerosol at the inlet is measured and controlled. Additionally, it has a second pump for the working fluid in order to suck it out of a large butanol reservoir. Due to those features it can operate for months without refilling the fluid reservoir.

The cut-off diameter is, as requested for ambient air monitoring CPCs, at 7 nm. Another advantage is the high aerosol flow rate of 1 l/min which reduces diffusion losses to a minimum. The ENVI-CPC 200 can be equipped with a powerful meteorological sensor that monitors ambient air temperature, pressure, humidity, wind speed, wind direction and precipitation type and intensity. A protective outdoor housing is available.

Fig. 1: Counting efficiency curve of the ENVI-CPC measured at the Leibniz Institute for Tropospheric Research

The control of the volume flow is enabled by an internal flow sensor with accessed long-life membrane pump. Contrary to a control with critical nozzle a contamination of the system does not lead to an drop of the volume flow. This is important especially for long-time measurements in ambient air. Additionally, the volume flow can be calibrated afterwards by the user.

As user interface the ENVI-CPC 200 has a 7“ touch display. For remote and network applications the ENVI-CPC 200 supports a standardised interface with different protocol choices, e.g. Modbus, Bayern-Hessen protocol and features like remote access and data storage in the internet or in an internal network.