MIL-PRF-11693 Capacitors, Feed Through, Radio-Interference Reduction, Dc \(Hermetically Sealed In Metal Cases\), Established And Non-Established Reliability General Specification ForThis specification covers the general requirements for established reliability \(ER\) and non-ER capacitors designed for operation with direct current \(dc\), paper, paper plastic, and plastic \(extended foil\) dielectric, radio-interference-reduction, feed-through capacitors, hermetically sealed in metal cases \(see 6.6.2\), for use primarily in broadband, radio-interference suppression application. Capacitors meeting the established reliability requirements specified herein have a maximum failure rate of 1.0 percent per 1,000 hours. This failure rate is established with a 90-percent confidence limit based on the life test parameters specified and are maintained at a 10-percent producer?╞s risk. An acceleration factor of 5:1 has been used to relate the life test data obtained at 140 percent of rated dc voltage at the applicable high test temperature to the rated voltage at the applicable high test temperature.

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MIL-PRF-11693E

e. Measurements during vibration: during the last half hour of vibration in each direction, a signal of 1 �0.2 kHz

at a level of 1 � 0.2 volts shall be placed across the capacitor and measured with a suitable device to

determine open-circuiting or short-circuiting or intermittent of 0.5 ms or greater duration.

f. Examination after test: Capacitors shall be visually examined for evidence of mechanical damage.

4.7.15 Moisture resistance (see 3.19). Capacitors shall be tested in accordance with method 106 of MIL-STD-202.

The following details and exceptions shall apply:

a. Initial measurements: Not applicable.

b. Polarization voltage: The dc potential shall be applied to either terminal and the case of 50 percent of the

capacitors. No potential shall be applied to the remaining 50 percent of the capacitors.

c. Final measurements: Upon completion of step 6 of the final cycle, the dielectric withstanding voltage,

insulation resistance at +25�C, capacitance, and dissipation factor shall be measured as specified in 4.7.4,

4.7.5, 4.7.6 and 4.7.7, respectively, at a relative humidity of 50 �5 percent.

d. Visual examination: Capacitors shall be examined for corrosion and obliteration of marking.

4.7.16 Solderability (see 3.20). Capacitors shall be tested in accordance with method 208 of MIL-STD-202. The

following details shall apply:

a. The number of terminations of each capacitor to be tested: 2.

b. Depth of immersion in flux and solder: Both leads/terminals shall be immersed to within 0.05 inches from the

solder seal.

4.7.17 Resistance to solvents (see 3.21). Capacitors shall be tested in accordance with method 215 of MIL-STD-

202. The following details shall apply:

a. Portion of specimen to be brushed: That portion on which marking is present.

b. Number of specimens to be tested: As specified in applicable inspection tables.

c. Permissible extent of damage: As specified in 3.21.

4.7.18 Low temperature and capacitance change at reduced temperature (see 3.22).

4.7.18.1 Low temperature. Capacitors shall be placed in a chamber maintained at -55� �3�C, and rated voltage at

the rated frequency (when applicable) shall be applied at this condition for 48 �4 hours (see 3.1). The air within the

conditioning chamber shall be circulated.

4.7.18.2 Capacitance change at reduced temperature. At the conclusion of the test specified in 4.7.18.1 but

before the capacitors are removed from the conditioning chamber, the capacitance shall be measured as specified in

4.7.6 except that the measurement shall be made at -55� �3�C. This measurement shall be compared with a

measurement made at room ambient temperature. After exposure, capacitors shall be visually examined for

evidence of breakdown, flashover, or fractures.

4.7.19 Life (see 3.23).

4.7.19.1 Qualification inspection. Capacitors shall be tested in accordance with method 108 of MIL-STD-202. The

following details and exceptions shall apply:

a. Method of mounting and distance between specimens: Suspended by their terminals with a distance of not

less than 1.5 inches separation between units.