Series S Polystyrene capacitors have superior electrical properties. They are dry-section, non-polar, non-inductive wound capacitors with low Dissipation Factor, low Dielectric Absorption, high Insulation Resistance and a low Temperature Coefficient. 

Series S Capacitors come in several styles: Oval Wrap & Fill (SW Style); Round Wrap & Fill (SR Style); Axial Epoxy Case (SE Style); Radial Epoxy Case (SF Style); Rectangular Hermetically Sealed (SG Style); Round Hermetically Sealed (SL Style). They are available in several sizes including Regular (3 Size code) and Miniature (2 Size code) as well as custom sizes to meet specific customer requirements. 

Contact our Engineering Department for special sizes, configurations, capacitance values and AC applications with Anti-Corona construction at all frequencies. Custom metal enclosures are available. Custom designed Feed Through capacitors (SQ Style) are also available for filter applications to specific requirements. 


Range: -55C to +85C, with voltage derating, 100% of the listed voltage rating from  -55C to +65C, derate linearly to 60% of the listed voltage rating at +85C.


Series S capacitors shall be capable of withstanding a test of 250 hours at +85C and 140% of the DC voltage or a test of 250 hours at +125C and 140% of the DC voltage. The voltage shall be applied to each capacitor through its individual current-limiting resistor as determined from the formula R = 0.025/C, where C is the nominal capacitance in farads and R is in ohms.

The test procedures shall be in accordance with MIL-C-19978, except as noted herein. Not more than one failure in twelve shall be permitted. Any one of the following shall be considered a failure.

  1. A change in capacitance of more than 6% from it's initial value.
  2. An increase in Dissipation Factor to a value greater than the initial acceptance limit.
  3. A decrease in Insulation Resistance to a value less than 60% of the acceptance limit for +25C.
  4. A permanent short or open


Series S capacitors shall be capable of withstanding a vibration test in accordance with MIL-STD-202, Method 201. The following details and exceptions shall apply: 

  1. Mounting. The capacitor body shall be rigidly mounted by the entire body length to the vibration test fixture. The leads shall be soldered to rigidly supported terminals and so spaced that the length of each lead from the capacitor is 1/2 1/8 inch from the edge of the supporting terminal. 
  2. Measurement during Vibration. During the last cycle in each direction, an electrical measurement shall be made to detect intermittent contacts (not to be confused with "self healing" clearings) or open or short circuiting.
  3. Examination After Vibration. Capacitors shall be visibly examined for evidence of mechanical damage. 


Series S capacitor Styles SG and SL (Hermetically Sealed in metal containers) as well as Metal Can Styles SB and SC shall be capable of withstanding the moisture resistance, humidity, and temperature and immersion cycling or MIL-C-19978. Styles SE and SF (Epoxy Case), Styles SW and SR (Wrap & Fill) and SQ (Feed-Through) capacitors are not intended for exposure to high humidity conditions over extended periods of time. 


Series S capacitors utilize tin-plated, copper-clad steel wire terminals which shall be capable of withstanding the following test without mechanical damage to the capacitor or terminals: 

  1. Pull Test. The capacitor shall withstand a steady pull of 5 pounds axially to the leads for 1 minute.
  2. Bend Test. The wire lead terminals shall be bent at a point of 1/4 inch from the body of the capacitor, first 90 degrees in one direction, then back to the original position, and then 90 degrees in the opposite direction.

Polystyrene and Foil Capacitor Graphs and Acceptance Criteria

Polystyrene and Foil Capacitors Size Index

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Updated: August 29, 1997

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Copyright © 1997 American Capacitor Corporation. All rights reserved.