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Operation manual ISOTEST 4 S / 4 S
p l u s
2. Special grounding methods
Testing plastic material
In most cases, welding seams will be tested when testing plastic material.
To allow using the high-voltage test method, coat the welding seam
and/or area with a electrically conductive material (grounding electrode).
Attach a grounding electrode to the entire rear of the area to be tested.
Pinholes and voids will safely be detected by sparking between the
testing electrode and the grounding electrode.
Required accessories:
Grounding foil
Part number 0174500100
Grounding cable Y - type
(clamping tongs - clamping tongs/plug)
Part number 0174250010
Application:
1. Cut the grounding foil to the required size.
Tear off the protective foil by holding at the edges, and fold one
corner. Glue the remainder of the grounding foil to the entire rear of
the welding seam or area to be tested, press against the test object,
and remove all air bubbles by wiping. Remove the protective foil step
by step.
2. Connect the plug of the Y grounding cable to the grounding
receptacle of the ISOTEST
®
test equipment.
3. Attach a pair of clamping tongs at the grounding cable to the folded
corner of the grounding foil, and attach the second pair of clamping
tongs to ground, ensuring a low-resistance path.
To obtain safe stress relief for the clamping tongs at the folded corner
of the grounding foil, secure the grounding foil with adhesive tape,
e.g., friction tape.
4. Turn the ISOTEST
®
test equipment on and perform the high-voltage
test. Remove the grounding foil after the test.
As an alternative to the grounding foil described above, you can also use
electrically conductive fleeces, grounding mats or grounding collars made
of electrically conductive rubber for testing of plastic parts.
The leakage test of containers can be performed using electrically
conductive liquids, e.g., saltwater, acids, etc.
Welding seams can also be tested by inserting a wire.
Grounding brushes are available for cylindrical test objects.
