1、 MIL-DTL-49285/20A 1 March 2010 SUPERSEDING MIL-C-49285/20 19 October 1989 DETAIL SPECIFICATION SHEET CABLE, SPECIAL PURPOSE, ELECTRICAL, TWO INDIVIDUALLY SHIELDED PAIRS OF 22 (7 X 30) AWG This specification is approved for use by all Departments and Agencies of the Department of Defense. The requir
2、ements for acquiring the product described herein shall consist of this specification sheet and MIL-DTL-49285. FIGURE 1. Cable illustration. AMSC N/A FSC 6145 INCH-POUND Inactive for new design after 16 June 1997. Provided by IHSNot for ResaleNo reproduction or networking permitted without license f
3、rom IHS-,-,-MIL-DTL-49285/20A 2 Engineering information: See table I. Note: Not for aerospace use. TABLE I. Description, electrical. Electrical characteristics Requirements Nominal capacitance between conductors Nominal capacitance between the conductor and the shield with one conductor tied to the
4、shield Continuous working voltage Nominal capacitance between adjacent shields Continuous working voltage between adjacent shields Shield dc resistance 35 pF/ft (picofarads/foot) 62 pF/ft 400 V rms maximum between conductors 150 pF/ft 50 volts maximum 19.5 ohms/1,000 feet maximum TABLE II. Descripti
5、on, physical. Components Construction details Number of pairs Conductor type and wire size Conductor stranding Conductor insulation Conductor insulation thickness Drain wire type and size Drain wire stranding Jacket material Jacket thickness Finished cable diameter Cable style (UL) Tensile strength
6、(jacket) Elongation (jacket) Overall cabling lay length Two individually shielded Stranded tinned copper 22 AWG 7 X 30 AWG Polypropylene 0.008 inch nominal thickness Stranded tinned copper 24 AWG 16 X 36 AWG Polyvinyl chloride 0.026 inch 0.216 inch maximum outside diameter 2717 2,000 pounds per squa
7、re inch minimum 150 percent minimum 9.5 twists per foot 10 percent Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-49285/20A 3 REQUIREMENTS: Design and construction: (see table II and figure 1): Shield location and orientation. The polyester
8、aluminum shield is to be located on the outer circumference of the pair, with the aluminum foil side outward. Insulation on the interior of the shield is to be complete with no aluminum available for contact. Drain wire location. The drain wire is to be spirally located between the noise reducing ta
9、pe and the aluminum foil shield, and is to be in continuous contact with the aluminum surface of the foil shield and the noise reducing tape throughout the cable. Cable temperature rating. The cable temperature rating shall be -20C to +80C. Shield integrity test.* Frequency Response * 100 kHz 112 dB
10、 below reference 500 kHz 105 dB below reference 1 MHz 99 dB below reference 5 MHz 83 dB below reference 10 MHz 76 dB below reference 15 MHz 73 dB below reference 20 MHz 71 dB below reference 25 MHz 67 dB below reference 30 MHz 63 dB below reference * Any two readings may deviate to a value of 0.9 ti
11、mes the stated limits. * All values are a minimum numerical value. Fixture resonance will occur between 40 and 70 MHz. At 100 MHz: At least 43 dB below reference. Crosstalk test limits. Crosstalk testing is not required for this configuration. Conductor color code. 1stpair 2ndpair 1stconductor: Red
12、1stconductor: Green 2ndconductor: Black 2ndconductor: White Shield color code. The shield color code shall be as follows: Pair number one: Blue Pair number two: Blue Overall shield: Blue Cabling. This construction shall be cabled on a common axis to reduce the diameter. Provided by IHSNot for Resale
13、No reproduction or networking permitted without license from IHS-,-,-MIL-DTL-49285/20A 4 Barrier tape. The individual pairs are to be covered with a plastic barrier tape applied over the pair shields. Insulation resistance between shields: 100 megohms/1,000 feet (minimum). Durometer hardness. The ca
14、ble jacket shall have a “Shore A” hardness of 82 5. Part or Identifying Number (PIN): The PIN shall be M49285/20. Changes from previous issue. The margins of this specification are marked with vertical lines to indicate where changes from the previous issue were made. This was done as a convenience
15、only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous issue. Referen
16、ced document. This document references MIL-DTL-49285. CONCLUDING MATERIAL Custodians: Preparing activity: Army CR DLA - CC Navy SH Air Force 85 DLA CC Review activities: Army MI Air Force - 71 (Project 6145-2009-005) DLA IS NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and responsibilities can change. You should verify the currency of the information above using the ASSIST Online database at http:/assist.daps.dla.mil. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-