MIL-DTL-49055F
4.6.11 High temperature aging. A cable specimen, 18±.5 inches (457± 13mm) in length, shall have
0.25±.10 inch (6.35 ±.25 mm) of insulation removed from each end. The central portion of the cable shall
then be bent at least halfway around a horizontally placed .25-inch (6.4mm) diameter stainless steel
mandrel. The stripped conductor ends shall be evenly clamped together so that the weight is suspended
from conductors only and the cable shall be loaded with the following weight so that the portion of
insulation between the conductors and mandrel is under compression while the conductors are under
tension.
Round wire
Weight (lb) per conductor
size (AWG)
(includes clamp weight)
24 through 28
0.1+0.03, -0.0
This specimen, so prepared on the mandrel, shall be conditioned in an air-circulation oven for 7 hours ±
15 minutes at the temperature specified (see table I). The velocity of air past the specimen shall be
between 100 and 200 feet per minute. The velocity may be measured with the oven off and at room
temperature. After conditioning, the oven shall be shut off, the door opened, and the specimen allowed to
cool in the oven for at least one hour. When cool, the specimen shall be freed from tension, the strips
removed, and the specimen removed from the mandrel. The central portion of the cable shall be bent at
least halfway around the mandrel so that the portion, which was outside during conditioning, is now next
to the mandrel. The cable shall be loaded with the applicable weight for one hour ±10 minutes at high
temperature (see table I). The cable shall then be removed from the mandrel and examined for cracking
and separation of the insulation. The specimen shall then be subjected to the dielectric withstanding
4.6.12 Flexing endurance. A specimen of cable having a length of six inches minimum shall be
installed in a fixture as shown on figure 3. An equivalent test fixture, with the approval of the qualifying
activity may be used. All conductors of the test specimen shall be electrically connected in series during
the test and a monitor current of 20±5 milliamperes shall be applied. A continuity tester capable of
indicating a current interruption of one microsecond shall be used to monitor the current. One end of the
cable shall be held in the fixed clamping device. The other end shall be fastened in the movable
clamping device, allowing a free length of 3 to 3.05 inches (76.2 to 77.5 mm) between clamping devices.
The movable clamp shall be driven in reciprocating linear motion for 5.4 to 5.5 inches (137 to 140 mm)
from one extreme position to the other extreme position. Cable and fixture shall be allowed to stabilize at
the test temperature for one hour before commencing test. One cycle shall consist of travel from one
extreme to the other and return. The specimen shall be subjected to a minimum of 25 cycles per minute
for the number of cycles and at the temperatures specified in the applicable specification sheet (see 3.1).
A different cable specimen shall be used for flexing at each temperature.
4.6.13 Moisture resistance. A specimen of cable 26 inches (660 mm) long shall be prepared as
specified in 4.6.4 and tested in accordance with method 106 of MIL-STD-202 (steps 7a and 7b shall not
be required). Following the tenth cycle, and while the specimen is still at environment, the wire to wire
insulation resistance shall be measured as specified in 4.6.5 with a potential of not less than 500 volts dc
applied for a minimum of one minute between each conductor and its next adjacent conductors.
Following the test, the specimen shall be examined.
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