The instrument contains a powerful, muffled suction pump drawing air through an interchangeable test head with a circular opening. For measurement the test head appropriate for the selected test standard is mounted to the instrument. The specimen is clamped over the test head opening by pressing down the clamping lever which automatically starts the suction pump. The preselected test pressure is automatically set and maintained, and after a few seconds the air permeability of the test specimen is digitally displayed in the pre-selected unit of measure. By pressing down the clamping lever a second time the test specimen is released and the suction pump is shutoff.
The air flow through the test specimen is measured with a variable orifice. The air permeability of the test specimen is determined from the pressure drop across this orifice, and is digitally displayed in the selected unit of measure for direct reading.
High stability, precision pressure sensors provide for an excellent measuring accuracy and reproducibility of the test results. The proper function and calibration of the instrument can be checked in a matter of seconds by means of a calibration check plate.
The instrument can be calibrated, and is supplied with an ISO conform calibration certificate. The long, free projection of the clamping lever (50 cm / 20") allows the operator to take measurements from large samples without having to cut small test specimens. By means of two extensions the working surface of the instrument can be increased to 120 x 60 cm.
Textest AG, PO Box 5523, Spartanburg, SC 29304. Tel: 864-595-0087; Fax: 864-595-0089.