1、MIL-E-24762 59 9999906 0479238 T -s a. - I DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. MIL-E-24762(SH) 28 May 1991 MILITARY SPECIFICATION ENCLOSURES FOR ELECTRONIC EQUIPMENT, SURVIVABLE, NAVAL SHIPBOARD USE This specification is approved for use by the Naval Sea
2、 Systems Command, Department of the Navy, and is available for use by all Departments and Agencies of the Department of Defense, 1. SCOPE 1.1 Scope. This specification establishes the design, development perfor- mance, and test requirements for survivable electronic enclosures for shipboard- surviva
3、ble electronic systems and equipment, is covered by this specification. Only one classification of enclosure 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.1 Specifications, standards, and handbooks. The following specifi- cations, standards, and handbooks form a part of this document to the
4、extent specified herein, those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation (see 6.2). Unless otherwise specified, the issues of these documents are SPECIFICATIONS FEDERAL PPP-F-320 - Fiberboard: Cor
5、rugated and Solid, Sheet Stock (Co- ntainer Grade) and Cut Shapes MILITARY MIL-R-900 - Rubber Gasket Material, 45 Durometer Hardness, MIL-S-901 - Shock Tests, H.I. (High-Impact); Shipboard Machinery, Equipment and Systems, Requirements for. I Beneficial comments (recommendations, additions, deletion
6、s) and any pertinent data which may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 5523, Department of the Navy, Washington, DC 20362-5101 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the
7、 end of this document or by letter. . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-_ _ _I MIL-E-24762 59 9999906 0479239 II MIL-S-1222 - Studs, Bolts, Hex Cap Screws, Socket Head Cap MIL-E-2036 - Enclosures for Electric and Electronic Equipment, M
8、IL-E-16400 - Electronic, Interior Communications and Navigation Screws and Nuts. Equipment, Naval Ship and Shore: General Specifi- cation for. and Provisioned Items (Repair Parts); Packaging of MIL-E-17555 - Electronic and Electrical Equipment, Accessories MIL-L-19140 - Lumber and Plywood, Fire Reta
9、rdant Treated MIL-W-21965 - Water Cooling of Shipboard Electronic Equipment General Specification for. STANDARDS MILITARY MIL-STD-108 - Definitions of and Basic Requirements for Enclosures for Electric and Electronic Equipment. MIL-STD-167-1 - Mechanical Vibrations of Shipboard Equipment (Type I - E
10、nvironmental and Type II - Internally Excited). Component Parts. Equipment. Requirements for the Control of Electromagnetic Interference. MIL-STD-470 - Maintainability Program for Systems and Equipment. MIL-STD-740-1 - Airborne Sound Measurements and Acceptance Criteria MIL-STD-810 - Environmental T
11、est Methods and Engineering Guide- MIL-STD-1310 - Shipboard Bonding, Grounding, and Other Techniques MIL-STD-1399 - Interface Standard for Shipboard Systems. MIL-STD-1399, - Interface Standard for Shipboard Systems Electric DOD-STD-1399, - Interface Standard for Shipboard Systems Electrical DOD-STD-
12、1399, - Interface Standard for Shipboard Systems Cooling MIL-STD-202 - Test Methods for Electronic and Electrical MIL-STD-454 - Standard General Requirements for Electronic MIL-STD-461 - Electromagnetic Emission and Susceptibility of Shipboard Equipment. lines, for Electromagnetic Compatibility and
13、Safety. Section 300 Power, Alternating Current. (Metric) Section 304 Cables and Connectors. Section 532 Water for Support of Electronic Equipment. (Metric ) MIL-STD-1686 - Electrostatic Discharge Control Program for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding E
14、lectrically Initiated Explosive Devices). (Metric) HANDBOOK MI LI TARY DOD-HDBK-263 - Electrostatic Discharge Control Handbook for Protection of Electrical and Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices). (Metric) 2 r I 1 1 1 E1 C L Provided by IHS
15、Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-247b2 57 777990b 0477240 8 (Unless otherwise indicated, copies of federal and military specifications, standards, and handbooks are available from the Standardization Documents Order Desk, Bldg. 4D, 700 Robbins
16、Avenue, Philadelphia, PA 19111-5094.) 2.1.2 Other Government documents. drawings. and Rublications. The following other Government documents, drawings, and publications form a part of this document to the extent specified herein. are those cited in the solicitation. Unless otherwise specified, the i
17、ssues NAVAL SEA SYSTEMS COMMAND (NAVSEA) 0900-074-4010 - TRIDENT CCS SPECIFICATION; Appendix 60.2: Measurement of Airborne and Structureborne Noise. - Handbook of Shipboard Electromagnetic Shield- ing Practice, STEPS No. S9407-AB-HBK-010. 0910-LP-047-6300 (Application for copies should be addressed
18、to the Standardization Documents Order Desk, Bldg. 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094.) 2.2 Non-Government Publications. The following document(s) form a part of this document to the extent specified herein. issues of the documents which are DOD adopted are those listed in the issue
19、 of the DODISS cited in the solicitation. documents not listed in the DODISS are the issues of the documents cited in the solicitation (see 6.2). Unless otherwise specified, the Unless otherwise specified, the issues of AMERICAN CONFERENCE OF GOVERNMENT AND INDUSTRIAL HYGIENISTS (ACGIH) ISBN 0-936-7
20、12-39-2 - Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents in the Work Environment. (Application for copies should be addressed to the American Conference of Government and Industrial Hygienists.) AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) F 1166 - Standard Practice f
21、or Human Engineering Design for Marine Systems, Equipment and Facilities (Application for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103). . (Non-Government standards and other publications are normally available from These docu
22、ments also the organizations that prepare or distribute the documents. may be available in or through libraries or other informational services.) 2.3 Order of Rrecedence. In the event of a conflict between the text of this document and the references cited herein, the.text of this document takes pre
23、cedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), both a preproduction and a production sample shall be subjected to first article inspection (see 6.4) in
24、accordance with 4.3 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-E-24762 59 = 999990b 0479241 T = . MIL-E-24762(SH) 3.2 Characteristics. 3.2.1 Performance. Enclosures shall provide support and protection of electronic equipment so that the
25、complete assembly shall withstand the shock and vibration stresses specified herein without any part of the assembly loosening, coming adrift, or otherwise creating a hazard to personnel or degrading operation of vital systems. 3.2.1.1 Protection. Enclosures shall provide protection of the integrate
26、d equipment so that the latter shall perform to design limits or simulation thereof after exposure of the complete assembly to the environmental stresses specified in 3.2.5 and the transportation stresses specified in 3.2.6. 3.2.1.1.1 Environmental stress. Grade A equipment as defined in MIL-S-901 s
27、hall perform to design limits during the environmental stress tests specified in 4.5.8 when properly integrated with the enclosure, (see 6.2), no equipment fault that is attributable to the stress shall occur in the grade A equipment for 100 operating hours after the stress episode. Unless otherwise
28、 specified 3.2.1.2 Electrical. Enclosures using electrical power shall comply with the relevant requirements of MIL-E-16400 and MIL-STD-1399, section 300. 3.2.1.3 Access times. Maximum access times shall be established for each enclosure opening, door, and access panel. Access times for each access
29、facility shall be tested during the maintainability demonstration (see 3.2.4.2). 3.2.2 Phvsical characteristics. 3.2.2.1 Accessibility. Enclosures shall support removable chassis, assemblies, and equipment. Enclosures shall provide access to all internal line replaceable units such as circuit card a
30、ssemblies and other replaceable subassemblies and parts, from the front without requiring disassembly of the enclosure or subassemblies. Drawers, hinged chassis, and other movable assemblies shall have mechanical locking stops in the maintenance positions. ground connections shall be readily accessi
31、ble when an item is open for main- tenance, Electrical and 3.2.2.2 Access panels. The number of fasteners provided to secure access panels, doors, and other openings shall be kept to the minimum consistent with mechanical, electrical, and electromagnetic compatibility (EMC) integrity of the enclosur
32、e (see 3.2.4.2). All such fasteners shall be captive, A positive means shall be provided to properly secure enclosure openings, doors, and panels after being opened for access. 3.2.2.3 Equipment requiring nroundinq. Equipment utilizing electrical power shall be connected to the ground system in acco
33、rdance with MIL-STD-454, requirement 1, and MIL-STD-1310. Unless otherwise specified (see 6.2), no con- venience outlets shall be provided with the equipment. If provided under these conditions, three conductors shall be used, with the green wire connected to the. cabinet or safety ground and with v
34、oltages obtained from an over-current protected utility power circuit separate from the equipment service power circuit. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-24762 59 m 9779906 0479242 I 3.2.2.4 Dimensional limitations. The overall
35、 size and form factors for the unit shall conform to the dimensional requirements specified (see 6.2). Electri- cal and piping connector protrusions shall not exceed 6 inches. No assembled and installed unit shall exceed a height of 72 inches, exclusive of connectors. 3.2.2.5 Weight. The weight of t
36、he unit shall be kept to a minimum commen- surate with good engineering design practices and the detailed requirements of the specification. 3.2.2.6 Degree of enclosure. The enclosure shall meet the degree of enclosure requirements as defined in MIL-STD-108, specified in MIL-E-16400, and as specifie
37、d in the contract or order (see 6.2). within the enclosure shall conform to requirement 31 of MIL-STD-454. The preclusion of moisture pockets 3.2.2.7 Heaters. Where necessary, automatic heaters shall be provided to prevent any adverse effects which might be caused by condensation or moisture penetra
38、tion when the system is secured, 3.2.2.8 Mountinq. Enclosures shall mount to a foundation that will be part of the ship structure. accordance with installation control drawings furnished as part of the enclosure design information.) Enclosure mounts (such as “C“ mounts) shall minimize requirements f
39、or opening or disassembly of the enclosure (which would invalidate factory acceptance or land-based test site verification). (The foundation will be fabricated by the installer in 3.2.2,8.1 Resilient mountinq. Unless otherwise specified (see 6.2), enclosures shall be designed for rigid mounting. If
40、resilient mounting is used, suitable damping shall be employed to withstand the shock and vibration environ- ments. Unless otherwise specified (see 6.2), the deck or other mounting surface shall be assumed to be rigid, 3.2.2.8.2 Internal support. All internally mounted assemblies shall have adequate
41、 support both front and rear (such as, shock pins, rack shelves, angle braces) to withstand shock and vibration stresses. Plug-in devices shall have positive restraints to prevent dislodging by shock or vibration. 3.2.2.8.3 Chassis slide support. Assemblies equipped with chassis slides shall employ
42、alternative means for support when in the closed position (such as, shock pins and cam blocks) so that the chassis slides do not bear a significant portion of the load under this condition. 3.2.2.8.4 Circuit card security. Circuit card assemblies shall be secured in a positive manner to preclude dis
43、lodgment, unseating, or breakage due to shock, vibration, thermal expansion, or any other cause except maintenance action. 3.2.2.9 Cooling. Enclosures shall be cooled in accordance with MIL-E-I6400 and the equipment specification. MIL-W-21965 except: as otherwise specified herein. tions shall be as
44、approved by the contracting activity. isolating the equipment from the cooling water system shall be part of the ships service piping. the cooling system completely by using the external couplings as vents. sible drains, such as weepholes and draincocks, shall be provided for removing water accumula
45、tion in enclosures and shall not adversely affect the environmental integrity of a unit. Water cooling shall meet the requirements of Cooling water piping connec- External valves for Internal vents shall be provided unless it is possible to fill Acces- 5 Provided by IHSNot for ResaleNo reproduction
46、or networking permitted without license from IHS-,-,- - - _ MIL-E-24762 59 m 9999906 0479243 3 3.2.2.9.1 Water fittings. For water-cooled equipment, supply and return water connections to the ships cooling water system shall be in accordance with MIL-W-21965. The equipment water fittings shall be lo
47、cated in positions that are readily accessible when the unit is installed in its intended environment. Enclosure drains shall be included as an integral portion of the enclosure design and shall be accessible from the front of each enclosure. 3.2.2.9.2 Emernencv coolinq. Water-cooled equipment shall
48、 have provisions for emergency cooling in accordance with MIL-W-21965. 3.2.2.10 Cabling. All external electrical connections shall be made by multicontact cable connectors meeting the requirements of this specification. The master keyway of each external connector shall be oriented toward the top or
49、 front of the enclosure. differently. Input and output interface connectors shall be keyed 3.2.2.11 Installation and interface. Interfaces with shipboard systems shall comply with MIL-STD-1399; at a minimum, the cooling water interfaces shall comply with section 532 and the electrical interface with section 304. component mounting hardware requirements in excess of grade 5 screws or bolts in accordance with MIL-S-1222 shall be identified and supplied with the enclosure.
