The measuring principle (verification of oil content)
Compressed air flows through the 20 nozzles of the impactor and vertically hits a baffle plate made from cut glass.
On account of the air being deflected 90° in the impactor, the aerosol particles are unable to follow the airflow due to their inertia and are separated on the glass plate.
The indentations in the cut glass are filled with oil, counteracting the light scattering caused by the cut glass. This principle provides a visual indicator of very low oil quantities.
Thanks to the special arrangement of the nozzles, it is possible to measure the quantity of oil separated. The measurement result is not depending upon oil type.
However, remember that oil aerosols solidify at increased temperatures and there are no visual signs of vapour. Although compressed air cools during depressurisation, this is not relevant for the specified temperature range.
Measurement and evaluation
- Connect the AEROTEST SIMULTAN HP breathing air tester to the compressor, the compressed air cylinder or the compressed air line.
- Prepare the breathing air tester by flushing through the compressed air to be tested for at least 3 minutes (without the impactor).
- The volume flow (4 l/min) is prescribed automatically by the breathing air tester.
- Slide the impactor into the connecting adapter as far as the stop.
- Insert the connecting adapter into the measuring instrument of the breathing air tester in the direction of the arrow (the open side of the adapters should point towards the measuring instrument).
- Insert the tester tubes into the measuring instrument of the breathing air tester.
- Take the measurement. Take the measurement for 5 minutes (use the breathing air tester’s stopwatch).
- Peel the protective film away from the impactor and read off the oil concentration.