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Low Voltage Distribution Transformers

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Low Voltage Distribution Transformers Your Presenters > Thomas Patzner Product Manager, Low Voltage Transformers > Marquette University – Electrical Engineering > Apprentice Electrician > Low Voltage Transformers - Co-op (Square D Company) (lab testing, inoperative trouble shooting, designing of units) - Application Engineer (Square D Company) - Sales Engineer (Jefferson Transformer) - Marketing (Square D Company) - Product Manager (Square D Company) 8 The Energy Policy and Conservation Act of 1975 (EPCA), as amended, prescribes energy conservation standards for various consumer products and certain commercial and industrial equipment, including distribution transformers. 9 EPACT 1992 • Authorized Department of Energy to evaluate Distribution Transformers Market Response • Energy Star – added Distribution Transformers to program – 1994 • NEMA – publishes Standard for Higher Efficient Transformers - 1996 • States Mandated NEMA Standard Level for Low Voltage Products (1999 through 2005) Department of Energy • DOE start analysis process • Advance Notice of Public Ruling – July, 2004 10 EPACT 2005 • Authorized DOE to mandate efficiency levels on Distribution Transformers • Low Voltage Transformers – Mandated to TP1 standard effected Jan, 2007 Market Response • Energy Star Program discontinued May, 2007 Department of Energy • DOE stop all work being done on Low Voltage units from the EPACT1992 • DOE finalized Medium Voltage Final Rule – 2007 – mandating levels effected Jan, 2010 • 10 CFR 431 includes how to test the distribution transformers • 10 CFR 429 -CERTIFICATION, COMPLIANCE, AND 11 ENFORCEMENT… COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution transformer means a transformer that— (1) Has an input voltage of 34.5 kV or less; (2) Has an output voltage of 600 V or less; (3) Is rated for operation at a frequency of 60 Hz; and (4) Has a capacity of 10 kVA to 2500 kVA for liquid-immersed units and 15 kVA to 2500 kVA for dry-type units; but… Liquid-immersed distribution transformer means a distribution transformer in which the core and coil assembly is immersed in an insulating liquid. Medium-voltage dry-type distribution transformer means a distribution transformer in which the core and coil assembly is immersed in a gaseous or dry-compound insulating medium, and which has a rated primary voltage between 601 V and 34.5 kV. Low-voltage dry-type distribution transformer means a distribution transformer that— (1) Has an input voltage of 600 volts or less; (2) Is air-cooled; and (3) Does not use oil as a coolant. 12 Distribution transformer means a transformer that— (5) The term “distribution transformer” does not include a transformer that is an— (i) Autotransformer; (ii) Drive (isolation) transformer; (iii) Grounding transformer; (iv) Machine-tool (control) transformer; (v) Nonventilated transformer; (vi) Rectifier transformer; (vii) Regulating transformer; (viii) Sealed transformer; (ix) Special-impedance transformer; (x) Testing transformer; (xi) Transformer with tap range of 20 percent or more; (xii) Uninterruptible power supply transformer; or (xiii) Welding transformer. 13 Distribution Transformer Liquid-immersed Dry-Type (2007 Final Rule) Low Voltage Medium Voltage EPACT 2005 (2007 Final Rule) Final Rule – April 2013 14 The ERAC subcommittee for medium voltage liquid-immersed, The ERAC subcommittee for low voltage distribution transformers and dry-type distribution transformers consisted of consisted of representatives of parties having a defined stake in the representatives of parties, listed below, having a defined stake outcome of the proposed standards and included: in the outcome of the proposed standards and included: > ABB Inc. > AK Steel Corporation > AK Steel Corporation > American Council for an Energy-Efficient Economy > American Council for an Energy-Efficient Economy > Appliance Standards Awareness Project > American Public Power Association > ATI-Allegheny Ludlum > Appliance Standards Awareness Project > EarthJustice > ATI-Allegheny Ludlum > Eaton Corporation > Baltimore Gas and Electric > Federal Pacific Company > Cooper Power Systems > Lakeview Metals > Earthjustice > Efficiency and Renewables Advisory Committee member > Edison Electric Institute > Metglas, Inc. > Fayetteville Public Works Commission > National Electrical Manufacturers Association > Federal Pacific Company > Natural Resources Defense Council > Howard Industries Inc. > ONYX Power > LakeView Metals > Pacific Gas and Electric Company > Efficiency and Renewables Advisory Committee member > Schneider Electric > Metglas, Inc. > U.S. Department of Energy > National Electrical Manufacturers Association > National Resources Defense Council > National Rural Electric Cooperative Association > Northwest Power and Conservation Council > Pacific Gas and Electric Company > Progress Energy > Prolec-GE > U.S. Department of Energy 15 10 CFR 431 – April 2013 Final Rule Conclusion Based on the analyses culminating in this final rule, DOE found the benefits to the nation of the standards (energy savings, consumer LCC savings, positive NPV of customer benefit, and emission reductions) outweigh the burdens (loss of INPV and LCC increases for some users of this equipment). DOE has concluded that the standards in today's final rule represent the maximum improvement in energy efficiency that is technologically feasible and economically justified, and would result in significant conservation of energy. 16 10 CFR 431 – April 2013 Final Rule Liquid-immersed Distribution transformers: A diversity of core materials are cost TSL 1 competitive and economically feasible for all Design Lines. TSL 2 EL 1 for all design lines TSL 3 Maximum efficiency achievable with M3 Steel TSL 4 Maximum NPV with 7% discounting TSL 5 EL 3 for all design lines Maximum source energy savings with TSL 6 positive NPV (7% discounting) TSL 7 Maximum technologically feasible (max tech) 17 10 CFR 431 – April 2013 Final Rule Liquid-immersed Distribution transformers: A diversity of core materials are cost TSL 1 competitive and economically feasible for all Design Lines. Phase Type Design line TSL Energy efficiency level Efficiency(%) count Liquid-immersed 1 1 1 1 (0.4 actual)* 99.11 2 1 Base (0.5 actual)* 98.95 3 1 1 (1.1 actual)* 99.49 4 3 1 99.16 5 3 1 99.48 18 10 CFR 431 – April 2013 Final Rule Low Voltage Distribution transformers: TSL 1 Maximum efficiency achievable with M6 Steel TSL 2 NEMA Premium Levels (CSL3-2004) Maximum efficiency achievable using butt lap TSL 3 core mitering for single-phase designs and full mitering for three-phase designs TSL 4 Maximum NPV with 7% discounting Maximum source energy savings with TSL 5 positive NPV (7% discounting) TSL 6 Maximum technologically feasible (max tech) 19 10 CFR 431 – April 2013 Final Rule Low Voltage Distribution transformers: TSL 2 NEMA Premium Levels (CSL3-2004) Phase Type Design line TSL Energy efficiency level Efficiency(%) count Low-voltage dry-type 6 1 2 Base 98.00 7 3 3 98.60 8 3 2 99.02 20 10 CFR 431 – April 2013 Final Rule Medium Voltage Dry Type Distribution transformers: TSL 1 EL 1 for all design lines A diversity of core materials are cost- TSL 2 competitive and economically feasible for all design lines TSL 3 Maximum NPV with 7% discounting Maximum source energy savings with TSL 4 positive NPV (7% discounting) TSL 5 Maximum technologically feasible (max tech) 21 10 CFR 431 – April 2013 Final Rule Medium Voltage Dry Type Distribution transformers: A diversity of core materials are cost- TSL 2 competitive and economically feasible for all design lines Phase Type Design line TSL Energy efficiency level Efficiency(%) count Medium-voltage dry-type 9 3 2 1 98.93 10 3 2 99.37 11 3 1 98.81 12 3 2 99.30 13A 3 1 98.69 13B 3 2 99.28 22 (a) Low Voltage Dry-Type Distribution Transformers 431.196 Energy conservation standards and their effective (1) The efficiency of a low- (2) The efficiency of a low- voltage, dry-type distribution voltage dry-type distribution dates. transformer manufactured on or transformer manufactured on or after January 1, 2007, but before after January 1, 2016, Low Voltage Distribution Transformers January 1, 2016 . Three Phase set at EL3 and EL2 (NEMA Single-phase Three-phase Single-phase Three-phase PREMIUM, CSL3-2004) levels from the Efficiency Efficiency Efficiency Efficiency DOE engineering analysis kVA (%) kVA (%) kVA (%) kVA (%) . Single Phase set at Base levels (no 15 97.7 15 97.0 15 97.70 15 97.89 change) from the DOE engineering analysis 25 98.0 30 97.5 25 98.00 30 98.23 . Minimum Levels of Efficiency at four 37.5 98.2 45 97.7 37.5 98.20 45 98.40 50 98.3 75 98.0 50 98.30 75 98.60 significant digits from three 75 98.5 112.5 98.2 75 98.50 112.5 98.74 (ie - .xxx to .xxxx) 100 98.6 150 98.3 100 98.60 150 98.83 167 98.7 225 98.5 167 98.70 225 98.94 250 98.8 300 98.6 250 98.80 300 99.02 333 98.9 500 98.7 333 98.90 500 99.14 Note 750 98.8 750 99.23 EL = Efficiency Level 1000 98.9 1000 99.28 CSL=Candidate Standard Level 23 (b) Liquid-Immersed Distribution Transformers. 431.196 Energy conservation standards and their effective (1) The efficiency of a liquid- (2) The efficiency of a liquid- immersed distribution immersed distribution dates. transformer manufactured on or transformer manufactured on or after January 1, 2010, but before after January 1, 2016 Liquid-immersed Distribution Transformers January 1, 2016, . EL1 (or lower) levels from the DOE Single-phase Three-phase Single-phase Three-phase engineering analysis Efficiency Efficiency Efficiency Efficiency kVA kVA kVA kVA . Note EL = Efficiency Level (%) (%) (%) (%) 10 98.62 15 98.36 10 98.70 15 98.65 15 98.76 30 98.62 15 98.82 30 98.83 25 98.91 45 98.76 25 98.95 45 98.92 37.5 99.01 75 98.91 37.5 99.05 75 99.03 50 99.08 112.5 99.01 50 99.11 112.5 99.11 75 99.17 150 99.08 75 99.19 150 99.16 100 99.23 225 99.17 100 99.25 225 99.23 167 99.25 300 99.23 167 99.33 300 99.27 250 99.32 500 99.25 250 99.39 500 99.35 333 99.36 750 99.32 333 99.43 750 99.40 500 99.42 1000 99.36 500 99.49 1000 99.43 667 99.46 1500 99.42 667 99.52 1500 99.48 833 99.49 2000 99.46 833 99.55 2000 99.51 24 2500 99.49 2500 99.53 (c) Medium-Voltage Dry-Type Distribution Transformers.
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