1、 MIL-DTL-49285/24A 1 March 2010SUPERSEDING MIL-C-49285/24 19 October 1989 DETAIL SPECIFICATION SHEET CABLE, SPECIAL PURPOSE, ELECTRICAL, FOUR INDIVIDUALLY SHIELDED PAIRS OF 22 (7 X 28) 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-49285/24A 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 27 pF/ft (picofarads/foot) 49 pF/ft 400 V rms maximum between conductors 150 pF/ft 50 volts maximum 14 ohms/1,000 feet maximum TABLE II. Description
5、, physical. Components Construction details Number of conductors 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 streng
6、th (jacket) Elongation (jacket) Overall cabling lay lengths Four individually shielded Stranded tinned copper 20 AWG 7 X 28 AWG Polypropylene 0.015 inch nominal thickness Stranded tinned copper 22 AWG 7 X 30 AWG Polyvinyl chloride 0.030 inch 0.380 inch maximum outside diameter Not applicable 2,000 p
7、ounds per square inch minimum 150 percent minimum 5.7 twists per foot 10 percent Cabled pair orientation: The position of the red and green pair shield shall determine the rotation direction for pair location (see figure 1). Provided by IHSNot for ResaleNo reproduction or networking permitted withou
8、t license from IHS-,-,-MIL-DTL-49285/24A 3 TABLE III. Shield color code. Pair numbers Shield color Center core 1stpair 2ndpair 3rdpair 4thpair Red Green Blue Blue REQUIREMENTS: Design and construction: (see table II): Shield location and orientation. The polyester aluminum shield is to be located on
9、 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 tape and the aluminum foil shield, an
10、d 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. Flammability. The cable shall pass UL 2556 flame test requirement. Shield integrity test.* Fre
11、quency Response * 100 kHz 110 dB below reference 500 kHz 102 dB below reference 1 MHz 95 dB below reference 5 MHz 80 dB below reference 10 MHz 73 dB below reference 15 MHz 69 dB below reference 20 MHz 65 dB below reference 25 MHz 62 dB below reference 30 MHz 59 dB below reference * Any two readings
12、may deviate to a value of 0.9 times the stated limits. * All values are a minimum numerical value. Fixture resonance will occur between 40 and 70 MHz. At 100 MHz: At least 47 dB below reference. Crosstalk test limits. Crosstalk testing is not required for this configuration. Frequency (kHz) Near end
13、 crosstalk (dB) Far end crosstalk (dB) 40 24 23 70 21 20 100 20 19 1,000 30 24 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-49285/24A 4 Conductor color code. 1stpair: 1stconductor: Red 2ndconductor: Black 2ndpair: 1stconductor: Green 2ndco
14、nductor: White 3rdpair: 1stconductor: White with red stripe 2ndconductor: White with black stripe 4thpair: 1stconductor: White with green stripe 2ndconductor: White with yellow stripe Polyester tape wrap. Each shielded pair is to be covered with a plastic barrier tape. Paper tape wrap. A paper barri
15、er tape is to be placed between the jacket and the cabled pair. Roundness. Fillers will be used to insure roundness. Insulation resistance between shields: 100 megohms/1,000 feet (minimum). Durometer hardness. The cable jacket shall have a “Shore A” hardness of 94 3. Part or Identifying Number (PIN)
16、: The PIN shall be M49285/24. 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 only and the Government assumes no liability whatsoever for any inaccuracies in thes
17、e 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. Referenced documents. In addition to MIL-DTL-49285, this document references the following:
18、 UL 2556. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-49285/24A 5 CONCLUDING MATERIAL Custodians: Preparing activity: Army CR DLA - CC Navy SH Air Force 85 DLA - CC Review activities: Army MI (Project 6145-2009-011) Air Force - 71 DLA IS
19、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-,-,-
