MIL-C-18312G
3. REQUIREMENTS
3.1 Specification sheets. The individual item requirements shall be as specified herein and in accordance with the
applicable specification sheet. In the event of any conflict between the requirements of this specification and the
specification sheet, the latter shall govern.
3.2 Qualification. Capacitors furnished under this specification shall be products that are authorized by the
qualifying activity for listing on the applicable qualified products list before contract award (see 4.4 and 6.3 ).
3.3 Materials. Materials shall be as specified herein. However, when a definite material is not specified, a material
shall be used which will enable the capacitors to meet the performance requirements of this specification.
Acceptance or approval of any constituent material shall not be construed as a guaranty of the acceptance of the
finished product.
3.3.1 Insulating, impregnating, and sealing compounds. Insulating, impregnating, and sealing compounds,
including varnish and similar materials, shall be chemically inactive with respect to the capacitor unit and the case
(see 3.4.3). The compound, either in the state of original application or as a result of having aged, shall have no
adverse effect on the performance of the capacitor. For liquid-filled capacitors (see 6.6.1), the same material shall be
used for impregnating as is used for filling.
3.3.2 Metals. Metals shall be of a corrosion-resistant type or shall be plated or treated to resist corrosion.
3.3.2.1 Iron and steel. The use of ferrous material for current-carrying parts shall not be permitted, except that
annealed copper-clad steel wire (30-percent minimum conductivity) may be substituted as terminal leads (see 3.4).
3.3.2 2 Dissimilar metals. Where dissimilar metals are used in intimate contact with each other, provision shall be
made to provide protection against electrolysis and corrosion. The use of dissimilar metal in contact, that may tend
toward active electrolytic corrosion (particularly brass, copper, or steel used in contact with aluminum or aluminum
alloy), shall not be acceptable; however, metal-plating or metal spraying of dissimilar metals onto base metals to
provide similar or suitable abutting surfaces, shall be permitted (for example, the spraying of copper on aluminum for
soldering operations, shall be allowed). The use of dissimilar metals separated by insulating material shall also be
permitted.
3.4 Design and construction. The capacitors and brackets shall be of the design, construction, and physical
dimensions specified (see 3.1).
3.4.1 Terminals.
3.4.1.1 Solder-lug terminals. Solder-lug terminals may be of any shape, provided dimensional limits are met, and
shall be coated with solder having a tin content of 40 to 70 percent.
3.4.1.2 Axial wire-lead terminals. Leads may be of solder coated solid copper wire, copper alloy, or copper clad
steel (see 3.3.2.1). Copper alloy or copper clad leads shall have a minimum of 30 percent of the conductivity of
electrolytic copper. The leads shall be coated with solder having a tin content of 40 to 70 percent.
3.4.2 Case. Each capacitor shall be enclosed in a hermetically sealed metal case that will protect the capacitor
element from moisture, impregnant leakage, and mechanical damage under the test conditions specified herein. The
use of exterior cardboard sleeves for insulating purposes shall not be permitted.
3.4.3 Capacitor element. The capacitor element shall consist of metallized paper, paper plastic, or plastic film.
The capacitor element may be separated by uncoated dielectric tissues.
3.4.3.1 Construction. All capacitors shall have extended electrode construction to minimize inductance.
4
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business