Search results
Results from the WOW.Com Content Network
Aircraft specific NATOPS manual cover. These manuals are typically about 2 inches thick. These are manuals for specific aircraft models containing standardized ground and flight operating procedures, training requirements, aircraft limitations, and technical data necessary for safe and effective operation of the aircraft.
HTML 4.01 Specification since PDF 1.5; HTML 2.0 since 1.2 Forms Data Format (FDF) based on PDF, uses the same syntax and has essentially the same file structure, but is much simpler than PDF since the body of an FDF document consists of only one required object. Forms Data Format is defined in the PDF specification (since PDF 1.2).
An example implementation given consists of copper rods buried 0.3-0.5m below ground, and spaced 3-7m apart. In situations where space is at a premium, or other difficulties prevent the construction of a proper grounding grid, ground rods may be driven in deeper, and a wire mat may also be used. [2]
The big advantage of the TT earthing system is the reduced conducted interference from other users' connected equipment. TT has always been preferable for special applications like telecommunication sites that benefit from the interference-free earthing. Also, TT systems do not pose any serious risks in the case of a broken neutral conductor.
A grounding transformer. A grounding transformer or earthing transformer is a type of auxiliary transformer used in three-phase electric power systems to provide a ground path to either an ungrounded wye or a delta-connected system. [1] [2] Grounding transformers are part of an earthing system of the network.
The primary reason for the use of isolated grounds (IG) is to provide a noise-free ground return, separate from the equipment grounding (EG) return. The EG circuit includes all of the metal conduit, outlet boxes, and metal enclosures that contain the wiring and must be grounded to provide a safe return path in case of fault currents.
The electrodes for electrical grounding are often called ground rods and are often made from steel with a copper clad surface – typically 1 to 2 m long and 20 millimetres (0.79 in) in diameter. These are driven vertically into the ground and bonded together with bare copper wire. [1]
It was not required to be used if a water pipe or other grounding electrode was present. In 1978, the NEC allowed 1/2 inch rebar to be used as a grounding electrode [NEC 250.52(A)(3)]. The NEC refers to this type of ground as a "Concrete Encased Electrode" (CEE) instead of using the name Ufer ground.