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ElektroPhysik
E-15
4.2 Preparing measurement
4.2.1 Cleaning the sample
The surface of the sample should be free of grease,
lacquer, oxide or passivation films. Use ordinary solvent
for cleaning. Oxide films can be removed by means of
alcohol or by means of the rubber pencil supplied with
the instrument.
Use ElektroPhysik PE 1 solution (accessories) or the
rubber pencil for removing chromate coatings on zinc
(see also paragraph 8.5 “Chromed zinc coatings”).
4.2.2 Postitioning the sample
The sample should be placed on the working surface
(35) in a stable position. Make sure that the measuring
cell can sit a right angles to the sample. If necessary,
the small part holder can be used (section 6).
Place an apporpriate rubber gasket (45) onto the outer
measuring cell (42). i.e. rubber gasket B (4 mm²) or the
rubber gasket with
∅
1,5mm if you use the mask C (1
mm²) or D (0,25 mm²).
Note:
To prevent erratic readings, the rubber gasket
∅
1,5 mm
should never be used without mask. The rubber gasket
has an area of 1,8 mm².
Release the stopper (34) at the measuring stand and
place the measuring cell onto the measuring sample.
Push the measuring cell holder (31) down until the
distance piece of the pressuer device (30) locks into
place.
Tighten the stopper (34).
Release the distance piece.
The built-in springs now exert a constant pressure of
the measuring cell on the sample. It is thus guaranteed
that the rubber gasket always keeps the same shape
and therefore the same measuring area. This is espe-
cially important when using the rubber gasket B (4 mm²)!