College of Science and Engineering
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Browsing College of Science and Engineering by Author "Anthony, Michael A."
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Item Right Sizing Commercial Electrical Systems(IEEE Industry Applications, 2016-07) Harman, Thomas L.; Anthony, Michael A.; Harvey, James R.For decades, the application of National Electrical Code (NEC) rules for sizing services, feeders, and branch circuits has resulted in unused capacity in almost all occupancy classes. U.S. Department of Energy (DOE) data compiled in 1999 indicate the average load on building transformers to be between 10% and 25%. More recent data gathered by the educational facilities industry have verified this claim. Recognizing that aggressive energy codes are driving energy consumption lower and that larger-thannecessary transformers create a larger-than-necessary flash hazard, the 2014 NEC provided an exception in Section 220.12 that permitted designers to reduce transformer kilovoltampere ratings and all related components of the power delivery system. This was a conservative, incremental step in the direction of reduced load density that is limited to lighting systems. Further study of feeder and branch circuit loading is necessary to inform discussions about circuit design methods in future revisions of the NEC.Item Rightsizing Electrical Power Systems in Large Commercial Facilities(IEEE Industrial and Commercial Power Systems, 2013) Harman, Thomas L.; Anthony, Michael A.; Harvey, James R.For decades, application of National Electrical Code (NEC) rules for sizing services, feeders and branch circuits has resulted in unused capacity in almost all occupancy classes. US Department of Energy data compiled in 1999 indicates average load on building transformers between 10 and 25 percent. More recent data gathered by the educational facilities industry has verified this claim. Recognizing that aggressive energy codes are driving energy consumption lower, and that larger than necessary transformers create larger than necessary flash hazard, the 2014 NEC will provide an exception in Section 220.12 that will permit designers to reduce transformer kVA ratings and all related components of the power delivery system. This is a conservative, incremental step in the direction of reduced load density that is limited to lighting systems. More study of feeder and branch circuit loading is necessary to inform discussion about circuit design methods in future revisions of the NEC.