REGISTRATION NR:3  Click here to print this document

300µm





Signal/Noise ratio, S/N = 20 (GK = 1,5)

Important!

This is a P type sensor registration, where the sensor constant has been selected to GK = 1,5.
The smallest detectable crack depth with a good signal/noise ratio, S/N, on a smooth surface, is approximately obtained by the following calculation:
DJspr = GK/50.
DJspr = 1,5/50 = 30µm (approx.).
Within limits, the crack signal S, is proportional to the crack depth.
For 0,075 mm deep crack, like in this case, with a S/N = 20, you will for example when S/N = 5, obtain a minimum detectable crack depth DJspr = 5/20 x 0,30 = 75µm (approx.) on machined/tooled surface!