Troubleshooting the Frazier® Differential Pressure Air Permeability Measuring Instrument

We offer a free online troubleshooting tips for the Frazier® Air Permeability Tester

Number One Rule:

Verify the proper operation of the Tester.

Test plates should be returned for calibration on a yearly basis.

Frequently verify the proper functioning of your Frazier Air Perm Tester by using one of the 9 standard test plates with its corresponding nozzle and check the reading that you obtain during the check with the calibrated reading on the Test Plate "calibration card" or "Test Plate Certificate of Calibration". These readings should be within plus or minus 3% of each other.

If you don't have a test plate for each of the nozzles that you normally use for testing then they can be purchased here.

Two:

Check the Nozzle Calibration.

Check the calibraton of each nozzle. To check the calibration of a nozzle you will have to first determine if your tester is functioning properly. You must also have a test plate that corresponds to the nozzle size that you are checking.

Check the nozzle and the test plate together and compare the the reading obtained with the test plate calibration. Record the results in the log. If the difference in the results is more than 3% then the nozzle should be cleaned and the nozzle should be rechecked. Record this result along with the "after cleaning" note. If the difference in the results is still more than 3% then the nozzle may be scratched in the bore and need to be recalibrated. Make sure to return the test plate to the protective enclosure.

Cleaning the Nozzle

Nozzles should not be cleaned with a solvent of any kind. Solvents will remove the finish and may change the calibration.

To clean the nozzle, thread a piece of cotton string through the hole and spin the nozzle around on the string.

 

FAQs

 

Are Test Openings Calibrated?

The test opening is not the part of this instrument that is calibrated. The test opening is simply the area of the test sample that is subject to airflow testing. The Nozzles (orifices) are each individually calibrated. Therefore any size test opening between 0.993" dia (5.000 sq cm) and 2.750" dia (38.323 sq cm) can be created and airflows from these custom size openings are based upon the standard size opening. If the instrument is in calibration with the 2.75" dia opening then it MUST be in calibration with these custom size openings. The calibration of each nozzle can be verified with its corresponding size Test Plate (Calibration Plate).

Testing the same sample on different size test openings at the same differential pressure (pressure drop) will yield the same airflow readings. Each differential size test opening will have its own corresponding calibration chart that must be used for that particular size test opening.