Walter SURFOX Owner's Manual page 11

For optimal results clean the area to be tested to remove residue and
dust, to keep the tip of the test probe clean.
3. Place the tip of the test probe on the area to be tested and the ground in
contact with metal.
4. Maintain the contact in position for the entire duration of the test (Fig. 6).
5. After testing, remove any residual electrolyte solution from the test area, using
a humid cloth.
N.B.: Typical values are +0.10 or higher for an AISI 304, for a carbon
steel (not stainless) - 0.55
NOTICE: It is well known that where a welding process occurred the heat treat-
ment altered the passivation of the stainless steel, forming a layer of non protec-
tive oxides, slug and iridescence. It is not recommended to use the tester in this
area, without prior cleaning, as they may cause false results due to the dielectric
behaviour of the non protective oxides and slug, risking to irreparably pollute the
tip and therefore distort the subsequent readings.
SURFOX Stainless steel passivation tester
Fig. 6
Owner's manual
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