3.8
SERVICE ENTRANCE PLATE
Install RF connectors from coaxial cable and other RF shielded cable on
entrance plate. Soft solder connectors to the plate. If location of plate
is not indicated, mount plate in wall panel adjacent to power line filters.
3.9
FIELD TESTS
3.9.1
Weld Testing
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NOTE: If the installation is critical, further
welding tests may be specified such as ultrasonic,
radiographic, or magnetic particle tests.
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Visually inspect welding during the welding operation and after the welding
is completed. Inspect completed welds after the welds have been thoroughly
cleaned by hand or power wire-brush. Inspect welds with magnifiers under
bright light for surface cracking, porosity, slag inclusion, excessive
roughness, unfilled craters, gas pockets, undercuts, overlaps, size, and
insufficient throat and concavity. Grind out defective welds and replace
with sound welds.
3.9.2
Seam Leak Detection Testing
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NOTE: SELDS testing the welds in the floor
shielding is usually very difficult because you
cannot "sniff" on both sides (assuming the shield is
on the ground level). To circumvent this problem
SELDS loops may be positioned beneath the floor
shield for SELDS testing. Dye penetrant has also
been used to test the welds and if the dye is used
properly this test can be as critical of a test as
SELDS.
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Continuously test welds during fabrication using the SELDS, commonly known
as a "sniffer." Upon completion of the basic shielded enclosure, before
applying any metal primer or installing any accessories, test the entire
shielded enclosure with the SELDS. Install terminal points on the
shielding exterior and permanently attach test leads on two sets of
diagonally opposing corners during construction for use with SELDS.
Continuously probe seams with the test receiver set to detect abrupt
changes of shielding level greater than 10 dB on the "shielding unit"
scale. Clearly mark points having change greater than 10 dB and repair the
weld to meet the specified requirement. Retest each repaired point until
there are no points on seams which fail test.
3.9.3
Attenuation Testing
[Furnish the services of an independent testing laboratory, approved by the
Contracting Officer, to test the shielded enclosure.] [Final acceptance
testing will be by the Government.] Conduct the final shielding acceptance
test after penetrations have been completed, specifically including
electrical and other utility penetrations. In addition, the Contractor may
schedule a complete or abbreviated test to verify that the shielding
SECTION 13094N
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