Power Distribution Systems - eaton.com

1 Design Guide SA081002EN Effective February 2019. Contents Systems Power Distribution system Design.. Basic Principles .. Trends in Systems Design.. Goals of system Design .. Designing a Distribution system .. Development of a system One-Line .. Importance of the system One-Line.. Standardized Drawing Symbols.. Additional Drawings, Schedules and Specifications .. Power system Voltages.. Voltage Classifications.. Incoming Service Voltage.. Incoming Service Considerations .. Utilization Voltage Selection.. Types of Systems .. Types of Systems .. Power system Analysis.. Systems Analysis.. Short-Circuit Currents General.. Fault Current Waveform Relationships.. Fault Current Calculations .. Fault Current Calculations for Specific Equipment Exact Method.

2 Application Quick Check Table.. Medium-Voltage Fuses Fault Calculations.. Low-Voltage Power Circuit Breakers Fault Calculations .. Molded-Case Breakers and Insulated Case Circuit Breakers . Fault Calculations.. Low-Voltage Circuit Breaker Interrupting Derating Factors .. Short-Circuit Calculations.. Determining X and R Values from Transformer Loss Data.. Voltage Drop .. system Protection Considerations .. Overcurrent Protection and Coordination.. Grounding/Ground Fault Protection.. Grounding.. Typical Components of a Power system .. Typical Power system Components.. Transformers .. Generators and Generator Systems .. Generator Short-Circuit Characteristics.. Generator Set Sizing and Ratings .. Generator Set Installation and Site Considerations.

3 Capacitors and Power Factor.. Motor Power Factor Correction.. Typical Application by Facility Type .. Healthcare Facilities.. Quick Connect Generator and Load Bank Capabilities.. Power Quality .. Power Quality Terms Technical Overview.. Other Application Considerations.. Seismic Requirements.. Reference Data.. Codes and Standards.. Suggested IEEE Designations for Suffix Letters.. Ampacities for Conductors Rated 0 2000 V. (Excerpted from NFPA 70-2014, ) .. Power Distribution Systems Design Guide SA081002EN. Effective February 2019. system Design Basic Principles Trends in Systems Design The growing impact of adverse weather conditions such as hurricanes and The best Distribution system is one that There are many new factors to consider in flooding is now driving incoming service will, cost-effectively and safely, supply the design of Power Distribution Systems .

4 And Distribution equipment rooms to adequate electric service to both present be located out of basements and other and future probable loads this section Federal and state legislation has been low lying areas. Regions prone to these is intended to aid in selecting, designing introduced to reduce the output of carbon storms often experience downed utility and installing such a system . emissions into the environment; the Power lines and/or flooded manholes, intent being the reduction of their impact resulting in a loss of Power to thousands The function of the electric Power on climate change. In order to address the of customers. In order to quickly return Distribution system in a building or an subsequent need for clean Power , there Power to these facilities, additional installation site is to receive Power at has been an accelerating trend toward on-site backup generation is being one or more supply points and to deliver the incorporation of solar and other included in both new designs and as it to the lighting loads, motors and all sustainable energy sources into existing upgrades to existing sites.

5 Other electrically operated devices. The and new building designs. Energy storage importance of the Distribution system Systems (ESS) are now making renewable This trend for resiliency is increasing to the function of a building makes it energy a more viable option by helping among grocery stores, large chain stores imperative that the best system be to stabilize Power output during transient and other Distribution facilities requiring designed and installed. dips or interruptions to Power production. refrigeration to keep products from spoiling as well as large multifamily In order to design the best Distribution Utility deregulation has also provided dwelling complexes in low lying flood system , the system design engineer financial incentives for building owners plain areas.

6 Must have information concerning the and facility managers to participate in loads and a knowledge of the types of peak demand load shaving programs. Building costs continue to rise and Distribution Systems that are applicable. These programs are intended to reduce rentable or usable space is now at a The various categories of buildings have load on the utility grid in response to a premium. To solve both problems, many many specific design challenges, but 1 hour or 1 day ahead signal from the design and construction firms are looking certain basic principles are common to utility. The users shedding or cycling of at off-site prefabrication of key elements. all. Such principles, if followed, will non essential loads is generally initiated Forest City Ratner's 32-story residential provide a soundly executed design.

7 By a building management system (BMS) complex adjacent to Barclay's Arena in in conjunction with Power monitoring Brooklyn, NY, advanced the modular The basic principles or factors requiring and lighting control equipment. To concept with individual building sections consideration during design of the Power ensure uninterrupted operation of key constructed at a factory off-site and Distribution system include: customer loads, incorporation of other erected by crane into place. Resiliency Functions of structure, present types of distributed generation such as from storms and floods involving the and future fuel cells and diesel or natural gas fired relocation of electrical equipment out reciprocating generator sets may be of flood prone areas is costly, time Life and flexibility of structure desired or required.

8 Consuming and takes up precious floor Locations of service entrance and space in a building. Electro Centers or Distribution equipment, locations and Hospital complexes and college campuses Integrated Power Assemblies (IPA) can characteristics of loads, locations of are increasingly adopting the design of be fitted out with a variety of electrical unit substations central utilities plants (CUPs). In lieu of a Distribution equipment and shipped to separate boiler plant, cogeneration is used the site in preassembled modules for Demand and diversity factors of loads to produce electricity and the wasted heat mounting on elevated foundation piles, Sources of Power ; including normal, from the combustion process is recaptured building setbacks or rooftops.

9 Standby and emergency to provide hot water for the campus. Continuity and quality of Power Large cogeneration plants (3 MW and Finally, the need to have qualified available and required above) often include large turbines or building electrical operators, reciprocating engines as their prime maintenance departments and facility Energy efficiency and management movers for the enhance engineers has collided with growing Distribution and utilization voltages service continuity, these generators use a expectations for improved productivity Busway and/or cable feeders continuous source of natural gas as their and reduced overall operating costs. The fuel supply. Cogen plants generally have increasing proliferation of smart devices Distribution equipment and higher Power conver sion efficiencies and and enhanced connectivity with Power motor control produce lower carbon emissions.

10 Distribution equipment has expanded Power and lighting panelboards facility owner's options. These capabilities and motor control centers allow for automated communication of Types of lighting Systems vital Power system information including Installation methods energy data, equipment wellness and predictive diagnostics, and electrical Power monitoring Systems equipment control. Electric utility requirements eaton Power Distribution Systems Design Guide SA081002EN. Effective February 2019. system Design The future Internet of Things promises Additionally, Article offers a OSHA has qualified a number of to add millions of more sensors and number of prescriptive alternative Nationally Recognized Testing other devices to collect operational methods for arc flash energy Laboratories (NRTL) to demon strate data and send it through the Internet reduction; one of which must be and certify product conformance to to cloud-based comput ing services.