IEEE C37.121-2012 pdf free

IEEE C37.121-2012 pdf free.IEEE Guide for Switchgear-Unit Substation-Requirements.
For the purposes of this document, the following terms and definitions apply. The IEEE Standards Dictionary: Glossary of Terms & Definitions should bc rcfcrcnccd for terms not defined in this clause.
articulated unit substation: A unit substation in which the incoming, transforming, and outgoing sections are manufactured as one or more subassemblies intended for connection in the field.
barrier: A partition within thc enclosure and part of thc contained equipment. used for the insulation or isolation of electric circuits or electric arcs.
conformance tests: Certain performance tests to demonstrate compliance with the applicable standards. The test specimen is normally subecLed to all planned routine tests prior to initiation of the conformance test program.
NOTE Thc conformance tests may. or may not. bc similar to certain design tests. I)emonstration of margin (capabilities beyond the slandardsl is not required.’
design tests: Tests performed to determine the adequacy of the design of a particular type, style. or model ut any unit of equipment. or its component parts, to meet its assigned ratings and to operate satisfactorily under normal service conditions or under any specified conditions. Such tests may also be used to demonstrate compliance with applicable standards of the industry.
NOTE 1—Design tests arc performed on rcpcescntatisc apparatus or prototypes to verify the validity of design analysis and calculation nieihods, and to substantiate the rulings assigned to all other apparalus of basically similar design. These tests are not intended to be performed on every design or during normal production. The applicable portion of these design tests may also be used to evaluate modifications of a previous design to assure that performance has not been advcrscly affected. Test data from previous similar designs may be used for current designs when appropriate. Once made, design tests need not be repeated unless the design is so changed as to modify performance.
NOTE 2—Design tests are sometimes called “type tests.”
enclosure: A surrounding case or housing used to provide a degree of protection to the enclosed conductors or equipment. and to provide a degree of protection to personnel against incidentally contacting live parts.
high voltage: A general term that pertains to the primary voltage, or primary-voltage side, of a transformer orofa unit substation.
incoming section: Equipment that includes necessary mechanical and electrical connecting parts for coordination in a unit substation on the high-voltage (or primary) side of a transformer section.
loss voltage: A general tenn that pertains to the secondary voltage, or secondary-voltage side, of a transformer or of a unit substation.
other tests: Tests, so identified in individual product standards, that may be specified by the user in addition to routine tests. (Examples: Impulse; insulation power factor; audible sound)
outgoing section: Equipment that includes necessary mechanical and electrical connecting parts for coordination into a unit substation on the low-voltage (or secondary) side of a transformer section.
primary unit substation: A unit substation in which the low-voltage section is rated above 1000 V.IEEE C37.121 pdf free download.