MIL-DTL-55302/174C
TABLE II. Contact plating requirements. 1/
Type
Finish requirement
A
Overall contact finish: Shall be gold in accordance with MIL-DTL-55302.
B
Localized contact finish: Contact engagement area shall have a minimum plating (see figure
2) in accordance with MIL-DTL-55302. Solder post area (contact type I, .195 minimum;
length; type IV, .135 minimum length) shall be tin-lead over nickel in accordance with
MIL-DTL-55302.
1/ Type C finish is deleted and superseded by type A or B.
REQUIREMENTS:
Design and construction:
Dimensions and configurations: See figure 1 and table I.
Materials: In accordance with MIL-DTL-55302.
Contacts: Shall be copper-beryllium in accordance with ASTM B194, ASTM B196/B196M, or
ASTM B197/B197M.
Plating: See table II and figure 2.
Current rating: 3.0 amperes maximum per contact, 2.25 amperes continuous per contact at room ambient with
no more than two adjacent contacts carrying this current.
Keying (see MIL-DTL-55302/31):
Two keys, Part or Identifying Number (PIN) M55302/31-04, and two retaining rivets, PIN M55302/31-05, are
recommended. Keys and screws shall be ordered separately.
Jackscrews (see MIL-DTL-55302/182):
Use M55302/182-08, or 10. Jackscrews are purchased separately.
Mating and unmating: The mating force in pounds shall be the number of contacts multiplied by .250; the
withdrawal force in pounds shall be a minimum of .025 times the number of contacts and shall not exceed the
measured insertion force.
Contact resistance: No individual contact pair shall have a resistance exceeding .015-ohm initial and .020 after
testing.
Contact retention: 3 pounds, minimum.
Dielectric withstanding voltage:
Sea level: 900 volts rms.
70,000 feet: 200 volts rms.
2 milliamperes maximum leakage current.
PIN: M55302/174 (and dash number from table I and type from table II).
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