Standard tests on motor vehicle passenger compartment filters

The volume flow is automatically regulated and adjustable from 60 to 800 m³/h.

With the aid of the CIF, both the fraction separation efficiency and the burden on the complete filters or filter media are measured and evaluated.

Particle dosing for the filter test is performed with the brush generator RBG 1000, which has been internationally established for over 30 years. On the CIF 3000, overall and fraction separation efficiency are determined with the high-resolution light scattering spectrometer Promo^® 3000.

The main advantage of the Promo ^® 3000 spectrometers lies in the use of fiber optic technology. This allows the sensor heads to be positioned directly at the measurement site, resulting in minimized line losses. Furthermore, with the aid of the Promo^® 3000, it is possible to use different sensors for raw gas and clean gas. With the Promo^® 3000 measuring systems, reliable tests to determine the separation efficiency and burden tests can be performed across the entire measurement range for all particle sizes.

Following ISO/TS 11155-1, the test rig is equipped with the salt aerosol generator AGK 2000. In the testing conduit, filter media up to a size of approx. 220 x 500 mm can also be tested under the conditions stated above. To test the influence of real ambient conditions on the separation behavior of filters, Palas^®offers an upgrade to the CIF test rig with climate technology components for adjustment of the temperature between +18 °C and +90 °C and the relative humidity between 30% and 70%.

As an option, the test rig can be upgraded after the provision of the measuring equipment for gas analysis for investigations of the adsorption and desorption dynamics following DIN 71460-2 and ISO/TS 11155-2.

The CIF 3000 is equipped with a high-pressure ventilator, which can be throttled on the pressure side with infinitely variable adjustment and is frequency-controlled and can be automatically regulated via the FTControl filter test software to regulate the volume flow. Furthermore, sensor data such as the volume flow, temperature, relative humidity, and differential pressure at the filter are also recorded automatically during the filter test. The aerosol generators and the corona discharge can be actuated via the FTControl software.

Fig 1: Example showing a comparison of fraction separation efficiencies

• Clear demonstration of the separation efficiency of your filters or filter medium throughout the entire measurement range from 0.2 to 40 µm with the Promo^® system
• Highest measurement reproducibility and repeatability highlight even fine differences in the separation efficiency
• Short measurement times of around 2 minutes per separation efficiency measurement thanks to optimized application
• Simple comparison of separation efficiency curves, calculation of mean values also possible

Fig. 2: Example of the hold time measurement

• Performance of measurements of the fraction separation efficiency during dust application; pressure loss or measurement time can be pre-selected as the abort criterion
• Determination and representation of the pressure loss and retention curves in a diagram and table form. Representing the particle diameters at 80% and 90% separation efficiency provides additional information.
• Comparison of the fraction separation efficiencies during the different burdening steps
• Shortening of the measurement times, e.g., through increased aerosol concentration