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|  MIL-R-19365D
d. Final measurements: At the end of the final cycle and while the resistors are still in the humidity
chamber at the high humidity condition, the resistance between the adjustable terminal and fixed
end terminals, total resistance, and insulation resistance shall be measured as specified in 4.7.1,
4.7.1.1, and 4.7.6, respectively. Resistors shall then be examined for evidence of mechanical
damage, breaking, cracking, spalling, loosening of terminals or mounting hardware. (The
subsequent 4 hours to 24 hours conditioning period and measurements do not apply).
4.7.11 Mechanical strength (see 3.16). Resistors shall be supported .125 inch (3.18 mm) from each
end and subjected to a transverse load of 50 pounds applied at the center of the resistor through a
fulcrum having a radius of not less than .250 inch (6.35 mm) nor more than .375 inch (9.53 mm). The
load shall not be applied on the exposed portion of the resistor. Resistors shall then be examined for
evidence of mechanical damage.
4.7.12 Terminal strength (see 3.17). Resistors shall be firmly clamped and a direct pull of 10 pounds
shall be applied to the hole of each fixed end terminal for at least 30 seconds, one terminal at a time, in
the direction away from the resistor and parallel to the longitudinal axis. Resistors shall then be examined
for evidence of mechanical damage, and breaking or loosening of terminals.
4.7.13 Life (see 3.18).
4.7.13.1 Test conditions . This test shall be conducted at an ambient temperature of 25 C 2C.
Resistors shall be mounted by means of their associated hardware, and wire leads shall be soldered to
their terminals to make connection for arranged that the temperature of any one res istor will not
appreciably influence the temperature of any other resistor. There shall be no circulation of air over the
resistors other than that caused by the heat of the resistors. The voltage used shall be the rated
continuous working voltage from an ac waveform (see 3.6), and adequate precaution shall be taken to
maintain constant voltage on resistors under test.
4.7.13.2 Procedure. Following a measurement of maximum engageable resistance (see 4.7.1.2), the
voltage shall be applied intermittently, 1.5 hours on and 0.5 hour off, for a total of 1,000 hours 12 hours.
This voltage shall be applied to the terminals specified in 4.7.1.2. Resistance measurements (see
4.7.1.2) shall be made at the end of the 0.5 hour off periods after 50 hours 4 hours , 100 hours 8 hours,
250 hours 12 hours, 500 hours 12 hours, 750 hours 12 hours, and 1,000 hours 12 hours have
elapsed. Resistors shall then be examined for evidence of mechanical damage.
5. PACKAGING
5.1 Packaging. For acquisition purposes, the packaging requirements shall be as specified in the
contract or order (see 6.2). When actual packaging of materiel is to be performed by DoD personnel,
these personnel need to contact the responsible packaging activity to ascertain requisite packaging
requirements. Packaging requirements are maintained by the Inventory Control Point's packaging activity
within the Military Department of Defense Agency, or within the Military Department's system Command.
Packaging data retrieval is available from the man aging Military Department's or Defense Agency's
automated packaged files, CD-ROM products, or by contacting the responsible packaging activity.
6 NOTES
(This section contains information of general or explanatory nature that may be helpful, but is not
mandatory.)
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