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|  MIL-R-19365D
6.1 Intended use. The resistors covered by this specification are military unique due to the fact that
these devices must be able to operate satisfactorily in military systems under the following demanding
conditions: 15 Gs of high frequency vibration, 100 Gs of shock (specified pulse), 25,000 cycles of
endurance at the maximum temperature, thermal shock (with no more than 5 percent deviation in initial
resistance), low temperature coefficient of resistance, and resistant to salt corrosion. In addition, these
military requirements are verified under a qualification system. Commercial components are not designed
to withstand these military environmental conditions.
6.2 Acquisition requirements. Acquisition documents must specify the following:
a. Title, number, and date of this specification, and the complete PIN.
b. Issue of DoDISS to be cited in the solicitation, and if required, the specific issue of the individual
documents referenced (see 2.1).
c. Packaging requirements (see 5.1).
d. Bracket assembly requirements (see 6.7.1).
6.3 Qualification. With respect to products requiring qualification, awards will be made only for
products which are, at the time set for opening of bids, qualified for inclusion in the applicable QPL
whether or not such products have been so, listed by the date. The attention of the contractors is called
to these requirements, and manufacturers are urged to arrange to have the products that they propose to
offer to the Federal Government tested for qualification in order that they may be eligible to be awards
contracts or orders for the products covered by this specification. The activity responsible for the QPL is
the Defense Supply Center, Columbus, DSCC-VQP, Post Office Box 3990, Columbus, OH 43216-5000.
6.4 Power dissipation. Resistors are rated in accordance with 4.7.7. When higher ambient
temperatures exist or when resistors are mounted in enclosures which limit ventilation, the wattage
dissipation of any resistor should be reduced in accordanc e with figure 1, so that the maximum
continuous operating temperature permissible for the resistor is never exceeded under the most severe
combination of temperature conditions (see 6.8).
6.5 Spacing. When resistors are mounted in rows or banks, they should be so spaced that, taking into
consideration the restricted ventilation and heat dissipation of the nearby resistors, none of the maximum
permissible continuous operating temperature. An appropriate combination of resistor spacing and
resistor power rating must be chosen if this is to be assured.
6.6 Supplementary insulation. When voltages greater than 500 volts dc, or 350 volts ac rms, are
present between resistor circuits and grounded surfaces on which resistors are mounted, supplementary
insulat ion capable of withstanding the voltage condition should be provided between resistors and
mountings and ground.
6.7 Mounting. Resistor should not be mounted by their terminals.
6.7.1 Bracket assemblies . When required (see 6.2), bracket assemblies (mounting hardware) are
available for these resistors under MS75009, "Bracket Assembly, Resistor (Power Type).
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