Roughness tester
Tesa
The mean roughness Ra matches the arithmetical mean of the absolute val-
ues related to the profile deviation y within the reference length l.
Max. profile valley depth Rmax (DIN 4768)
The max. profile valley depth Rmax counts for the most significant single
roughness depths Zi within the total length lm.
According to ISO 4288 and DIN 4287 - Part 1, this parameter is also
specified as Ry max.
