Lorenz Messgerätebau

Lorenz company profile


Products :

Aerosol measuring technology

Aerosol generation

Filter testing

Smoke alarm testing

Bulk material assessment

Ringer Bath Handler

Bundesstrasse 116 - 37191 Katlenburg-Lindau - +49(0)5556/1093

deutsche Version
Products - filter testing  

<ViScan LP2>
<Filter measuring device FMP 03>
<Automatic measuring set FMP 03 + FH>

ViScan LP2 - New Oil Thread Test Device for Particle Filters
Lorenz Messgerätebau introduces a new oil thread test device which uses a new technique for testing particle filters in accordance with EN DIN 1822: The ViScan LP2. The new device uses state-of-the-art video and laser components in combination with a PC-based image processing software to detect leaks. Many other systems require an operator with good observing skills to recognize and find oil threads originating from leaks. Besides the fact that the search for weak oil threads can become very eye-tiring the detection of small leaks is a more difficult task.
In our new system we've replaced the human eye with a high-sensitive video camera. The camera is mounted inside a light tight cabinet directly over the adapter plate which holds the filters to test.
    The detection of leaks is performed by a personal computer and our special image processing software.
    This new concept is space-saving, time-saving and detects every leak down to the detection limit of the camera (which depends on the aerosol concentration of the raw air, the size of the leaks and the like). Additionally, the leak test creates an detailed leak-image from every filter analyzed which can be stored on harddisc for further studies and investigations.
    The ViScan LP2 device works half automated. The measurement procedure is very simple and only a few steps are necessary to conduct a complete measurement cycle: The operator puts the filter to test into position and presses two buttons simultaneously to trigger pneumatic levers which push the filter tightly down onto the adapter plate. In a second step the operator hits another button to run the measurement. A laser beam scans the entire surface of the filter for leaks. The video camera detects the leaks and stores them. As soon as the measurement ends the detected leaks are displayed and copied into the video image of the filter. This way all detected leaks can be sealed easily by the operator after the measurement. Optionally the ViScan LP2 device can be equipped with a differential pressure transducer to display the pressure drop of the filter.
    The ViScan LP2 allows to test filters with a size of up to 600 by 600 mm and heights of up to 300 mm. Different filter adapter plates for different filter sizes and shapes are easily exchangable. To be operational the ViScan LP2 needs to be supplied with the required aerosol flow rate generated by an air processing unit and an aerosol generator. These devices can also be purchased from Lorenz Messgerätebau.

top Filter measuring device FMP 03
ViScan LP2

Filter measuring device FMP 03
The FMP03 generates the test aerosol in the required concentration with standard-compliant particle size distribution.

  • It determines the separation efficiency of the filter sample,
  • measures the filter resistance with the volumetric flows specified in the relevant standards,
  • compares the measured values with corresponding limiting values and
  • assesses and logs the results.

The FMP03 is ideal for automating your filter tests. Its process control computer can provide either analogue or digital inputs and outputs to control your test station. We would be happy to adapt the FMP serial products to suit your testing specifications.
top Filter measuring device FMP 03
Filter measuring device FMP 03

Automatic measuring set FMP03 + FH
for quickly testing particle filters and filter media.

The filter measuring set consists of 2 components:

  • Filter measuring device FMP 03 and
  • universal filter holder FH-143/149 automatic


  • Short testing times (approx. 10 seconds per filter) and extremely simple operation
  • The separation efficiency and filter resistance of the sample are determined in a sample clamp.
  • The plant process control computer carries out the test on its own according to the user's specifications.
  • The test is carried out automatically according to the specified test standards, either with a fixed or different volumetric flows, with uniform or different aerosol concentrations or with uniform or different flow directions.
  • The process control computer assesses the sample.
  • The only thing the operator has to do is insert and remove the sample.


  • For production controls and type testing, e.g. testing filter respirators and filtering half-mask facepieces with liquid paraffin aerosol according to standards EN 143 and EN 149.
  • Leak testing and filter resistance tests on particle filters to a maximum diameter of 200 mm. Very good correlation to corresponding measurements according to EN 1822.
top Automatic measuring set FMP03 + FH
Automatic measuring set
FMP03 + FH