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IEEE Guide for Switchgear--Unit Substation--Requirements (Published), 2020
- IEEE Std C37.121™-2020 Front cover
- Title page
- Important Notices and Disclaimers Concerning IEEE Standards Documents
- Participants
- Introduction
- Contents
- 1. Overview [Go to Page]
- 1.1 Scope
- 1.2 Purpose
- 1.3 Word usage
- 2. Normative references
- 3. Definitions
- 4. Service conditions [Go to Page]
- 4.1 General
- 4.2 Usual service conditions
- 4.3 Unusual service conditions
- 5. Transformer section [Go to Page]
- 5.1 General
- 5.2 Primary unit substation transformers
- 5.3 Secondary unit substation transformers
- 6. Incoming section [Go to Page]
- 6.1 General
- 6.2 High-voltage (or primary) bushings on the transformer cover
- 6.3 Primary terminal chamber on the transformer
- 6.4 Metal-enclosed bus
- 6.5 Metal-clad or metal-enclosed switchgear
- 6.6 Metal-enclosed interrupter switchgear
- 6.7 Cutout, fuse, or fuse link
- 6.8 Metal-enclosed switchgear incorporating gas insulation systems
- 7. Outgoing section [Go to Page]
- 7.1 General
- 7.2 Metal-clad switchgear
- 7.3 Metal-enclosed interrupter switchgear
- 7.4 Metal-enclosed bus
- 7.5 Metal-enclosed, low-voltage, power circuit breaker switchgear
- 7.6 Switchboards
- 7.7 Motor control centers
- 8. Ratings [Go to Page]
- 8.1 General
- 8.2 Rated power frequency
- 8.3 Rated kVA
- 8.4 Rated high voltage (or primary voltage) and rated low voltage (or secondary voltage)
- 8.5 Rated continuous current
- 8.6 Rated short-time withstand current
- 8.7 Rated momentary withstand current
- 8.8 Rated power frequency withstand voltages
- 8.9 Rated lightning impulse withstand voltage (BIL)
- 9. Construction [Go to Page]
- 9.1 General
- 9.2 Phase and polarity arrangements
- 9.3 Phase sequence
- 9.4 Metal barriers
- 9.5 Interlocks
- 9.6 Grounding
- 9.7 Nameplates
- 9.8 Drawings, diagrams, instructions
- 9.9 Coordination
- 10. Typical arrangements [Go to Page]
- 10.1 General
- 10.2 Primary unit substations
- 10.3 Secondary unit substations
- 11. Guide for selection, application, installation, and maintenance of unit substations [Go to Page]
- 11.1 Application considerations
- 11.2 Unusual service conditions
- 11.3 System conditions
- 11.4 Transformer selection
- 11.5 Load requirements
- 11.6 Miscellaneous design considerations
- 11.7 Installation, field-testing, operation, and maintenance
- Annex A (informative) Bibliography
- Back cover [Go to Page]