MIL-PRF-83421 Capacitors, Fixed, Metallized, Plastic Film Dielectric, \(Dc, Ac, Or Dc And Ac\), Hermetically Sealed In Metal Cases Or Ceramic Cases, Established Reliability, General Specification ForThis specification covers the general requirements for established reliability \(ER\), metallized plastic film dielectric, fixed capacitors, hermetically sealed in metal or ceramic cases. Capacitors covered by this specification have failure rate levels \(FRL\) established in accordance with MIL-STD-690. The reliability for each level is identified by a symbol in accordance with table I. These FRLs are established at a 90 percent confidence level and maintained at a 10 percent producer\'s risk and, unless otherwise specified \(see 3.1\), are based on life tests performed at maximum rated voltage at maximum rated temperature. Unless otherwise specified \(see 3.1\), an acceleration factor of 5:1 has been used to relate life-test data obtained at 140 percent of rated voltage at maximum rated temperature, to rated voltage at maximum rated temperature \(see 6.1\). A part per million \(PPM\) quality system is used for documenting and reporting the average outgoing quality of capacitors supplied to this specification. Statistical process control \(SPC\) techniques are required in the manufacturing process to minimize variation in production of capacitors supplied to the requirements of this specification.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11

MIL-PRF-83421E

d. Measurements during and after shock: During the test, a cathode-ray oscilloscope (or other comparable

means) shall be used as an indicating device in determining any electrical failures and intermittent contacts of

0.5 ms or greater duration, open-circuiting or short-circuiting. Dissipation factor shall be measured as

specified in 4.7.9 and shall be within initial limits.

After the test, capacitors shall be visually inspected for evidence of breakdown, arcing, fractures, and other visible

mechanical damage.

4.7.17 Resistance to soldering heat (see 3.21). Capacitors shall be tested in accordance with method 210 of

MIL-STD-202. The following details shall apply:

a. Depth of immersion in molten solder: To a minimum of .250 inch from the capacitor body.

b. Test condition letter C, except test time shall be 10 �1 seconds.

c. Cooling time prior to final measurement: Sufficient time to stabilize at room temperature.

d. Measurements after test: Insulation resistance, capacitance, and dissipation factor shall be measured at

+25�C �3�C as specified in 4.7.7, 4.7.8, and 4.7.9, respectively.

4.7.18 Moisture resistance (see 3.22). Capacitors shall be tested in accordance with method 106 of MIL-STD-202.

The following details and exceptions shall apply:

a. Mounting: As specified in 4.7.11a. Capacitors which are normally supported by their wire leads shall be

mounted to rigidly supported terminals so spaced that the length of each lead from the capacitor body shall

be approximately .625 inch. Tubular capacitors greater than .562 inch nominal diameter and 1.562 inches in

length shall have a supplementary mounting means, and the leads shall be supported at the ends during

vibration.

b. Subcycle: A total of five subcycles shall be performed. The vibration required in step 7 shall be in any

direction.

c. Loading (polarization): During steps 1 to 6 inclusive, a dc potential of 100 volts or rated voltage (see 3.1),

whichever is less, shall be applied across the terminals of 50 percent of the capacitors. No potential shall be

applied to the remaining 50 percent of the capacitors.

d. Final measurements: After the final cycle, capacitors shall be conditioned at +25�C +10�C, -5�C at a relative

humidity of less than 80 percent, and a barometric pressure between 28 and 32 inches of mercury. After a

maximum of 24 hours, capacitors shall be inspected for evidence of extensive corrosion, and unwrapping of,

or mechanical damage to the insulating sleeves.

Dielectric withstanding voltage and insulation resistance shall be measured only on the insulating sleeves of

case sizes .400 inch diameter x 1.063 inch long and larger at +25�C �3�C as specified in 4.7.6 and 4.7.7,

respectively, except the measurements shall be made between two wire windings placed around the sleeve

of the capacitor .500 inch apart; each winding shall consist of three close turns of .040 inch (18 AWG) bare

copper wire.

All capacitors shall have dielectric withstanding voltage, insulation resistance, capacitance, and dissipation

factor shall then be measured at +25�C �3�C as specified in 4.7.6 through 4.7.9. These tests shall be done

with insulating sleeves removed.

After the test, capacitors shall be visually inspected for evidence of extensive corrosion, and unwrapping of,

or mechanical damage to the insulating sleeves.