Proceq PM8500 User Manual page 32

Figure 28 : PM8500 Profometer App: Statistic View
If the surface under test has both actively corroding as well as passive rebars, then the two
states exhibit two distinct partially overlapping distributions, with the corroding areas centered
on a more negative potential.
The cumulative distribution graph is used to determine the active and passive potential
thresholds that will affect the Chipping Graph, discriminating actively corroding areas from
passive areas where no corrosion is to be expected. If the surface under test has both actively
corroding as well as passive rebars, then the curve will typically exhibit a central region with a
lower gradient (flatter). The two points where the gradient changes can be marked on the
screen by dragging the two vertical cursors.
The red cursor will define the maximum (most positive) potential value expected of the active
distribution. Active corrosion is to be expected in the region of the left hand (more negative)
straight section.
The green cursor will define the minimum (most negative) potential of the passive distribution.
Once these cursor lines have been set, the surfaces in this potential range will be automatically
displayed in the corresponding color in the Chipping Graph View.
25. September 2023 © Copyright 2023, PROCEQ SA 32