Plugs for use with metal cased portable tools and equipment should have provisions for automatically grounding the metal frame or case of tools and equipment when the plug is mated with receptacle, and the grounding pin should make first, break last. Ground connections to shields, hinges, and other mechanical parts should not be used to complete electrical circuits. Any external or interconnecting cable, where a ground is part of the circuit, should carry a ground wire in the cable terminated at both ends in the same manner as the other conductors. In no case, except with coaxial cables, should the shield be depended upon for a current-carrying ground connection. Static and safety grounds should not be used to complete electrical circuits. A point on the electrically conductive chassis or equipment frame should serve as the common tie point for static and safety grounding. The path from the tie point to ground should:
a. Be continuous and permanent.
b. Have ample carrying capacity to conduct safely any fault currents that may be expected to be imposed on it by internally generated faults.
c. Have impedance sufficiently low to limit the potential above ground and to facilitate the operation of the over current devices in the circuits, and;
d. Have sufficient mechanical strength of the material to minimize possibility of ground disconnection.
Replaced/Superseded by document(s)
|File||MIME type||Size (KB)||Language||Download|
|DoD Handbook- General Guidelines for Electronic Equipment (2007).PDF||application/pdf||5.1 MB||English||DOWNLOAD!|
1. This handbook is approved for use by all Departments and Agencies of the Department of Defense
2. This handbook is for guidance only. This handbook cannot be cited as a requirement. If it is, the contractor does not have to comply.
3. This handbook is the technical baseline for the design and construction of electronic equipment for the Department of Defense. It captures in one document, under suitable subject heading, fundamental design guidelines for multiple general electronic specifications. The opportunity to focus on a single document, afforded to contractors, results in substantial savings to the Government. This handbook was prepared by, and is regularly updated through, the cooperative efforts of Government and industry. The documents listed below are not necessarily all of the documents referenced herein, but are those needed to understand the information provided by this handbook.
• DOD-E-8983 Electronic Equipment, Aerospace, Extended Space Environment, General Specification for.
• MIL-F-18870 Fire Control Equipment, Naval Ship and Shore, General Specification for.
• MIL-PRF-28800 Test Equipment for Use with Electrical and Electronic Equipment, General Specification for.
• MIL-HDBK-2036 Electronic Equipment Specifications, Preparation of.