CONSIDERATIONS WHEN SPECIFYING A …

1 CONSIDERATIONS when SPECIFYING A TRANSFORMERzApplicationzConfigurationzIn ternal ConstructionzDielectric FluidzAccessoriesAPPLICATIONzDistributio n Running lights, HVAC, OfficezMotor Control CenterzDedicated Load Pump, CrusherzExtreme Duty Drag-lineAvailable ConfigurationsAvailable ConfigurationszzPadmountPadmountzzStatio nStationzzSecondary Unit SubstationSecondary Unit SubstationzzSpecialtySpecialty Grounding, Rectifier, Mine DutyShell vs. Core Form TransformersRectangular vs. Round Coil ConstructionDisk WoundINTERNAL CONSTRUCTIONS hell form & core form transformer constructionShell form & core form transformer construction- 3 legged stacked core-Each phase shares a core bar. Harmonic content can lead to tank heating if wye/wye connected. -5 legged wound core-Each phase has a magnetic flux return path independent from the other Std definitions:Shell form: A transformer in which the laminationsconstituting the iron core surround the windings and usually enclose the greater part of form.

2 A transformer in which those parts of theMagnetic circuit surrounded by the windings have theForm of legs with 2 common & core transformersShell & core transformersRectangular coil & 5 legged core assemblyRectangular coil & 5 legged core assemblyDistributed gap core constructionDistributed gap core constructionCore after shear operation Distributed gapsDistributed gap core constructionDistributed gap core constructionRaw stock core materialDistributed gap core constructionDistributed gap core constructionPressed cores queued for annealingLoading the annealing ovenAnnealed coresDistributed gap core constructionDistributed gap core constructionRectangular coilsRectangular coilsCooling ductsCore windowsHV tapsHV finishHV startLV windingLV leadsxxxx2x2x2x2xRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresStacking the distributed gap coresAnnealed Laminations212345 Application of core frameRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresAssembled 5 legged distributed gap core and coil assemblyOuter core legs and core frameRectangular coils w/ distributed gap coresRectangular coils w/ distributed gap coresShell & core transformersShell & core transformersRound core and coil assemblyRound core and coil assemblyTop view.

3 Single core/coilCruciform core shearCruciform core shearCruciform stacked core constructionCruciform stacked core constructionCruciform core constructionCruciform core constructionTop viewYoke - leg interfaceCruciform stacked core constructionCruciform stacked core constructionCruciform coreRound CoilsRound Coils360 degree cooling ductsRound CoilsRound CoilsRadial forces are equalized during short circuits & overloadsCore Core Coil AssemblyCoil AssemblyImproved coolingcore frame insulationCore Core Coil AssemblyCoil AssemblyRound coils with cruciform coreRound coils with cruciform coreHV leads & tapsLV leadsTop yokeRound coils with cruciform coreRound coils with cruciform coreTanking assembled core & coil assemblyDisk-Type Coil WindingDisk Coil ConstructionStatic PlateStatic PlatePB WasherWinding Tube Inner DiameterWound DiameterCoil Inner DiameterCoil sectionTube ExtensionWinding TubeWinding SpaceRadial SpacersOutside Vertical SpacerVertical SpacerMDMCWDRBR adial SpacerOutside Vertical SpacerVertical SpacerWinding TubeContinuous DiskHelical DiskStages of Disk Windings AssemblyConstruction comparisonsConstruction comparisonsRectangular coil Rectangular coil --5 legged core advantages5 legged core advantagesWith strip conductor secondaries: HV electrically centered on the LV windingHV electrically centered on the LV winding Significant gain in mechanical strengthSignificant gain in mechanical strength Suitable for high volume productionSuitable for high volume production No tank heating from stray flux inductionNo tank heating from stray flux inductionin tank in tank wall when connected wyewall when connected wye--wyewyeRound coil Round coil --cruciform core usescruciform core usesWith wire / wire windings.

4 Means of providing increased hoop strength Means of providing increased hoop strength Enables solid construction of higher kVA unitsEnables solid construction of higher kVA units Suitable for small power designs & dedicated loadsSuitable for small power designs & dedicated loads Reduction in width dimension for retrofit Reduction in width dimension for retrofit applications applications Round Coil/Cruciform Core Advantages 360 degree cooling Increased insulation life More efficient cooling during heavy duty cycles Top & bottom pressure plates Containment of axial forces during short circuits Round coil construction Maximum containment of radial forces during short circuits Improved clearances between phases Dielectric FluidszMineral Oil (Type II)zVegetable-Based Oil (Envirotemp FR3) High Fire Point (300 degrees C) BiodegradablezSiliconezVoltesso Lower Temperature Pour PointStandard AccessorieszOil Temperature GaugezLiquid Level GaugezPressure/Vacuum GaugezPressure Relief ValvezDrain Valve w/ Sample PortzUpper Fill PortzAir Space filled with Dry NitrogenOptional Accessories Part 1zDry Contacts on GaugeszPressure Relief DevicezForced Air Cooling 15% increased capacity 2499 kVA and smaller 25% increased capacity 2500 kVA and largerzWinding Temperature GaugezSudden Pressure Rise Relay Seal-In RelayOptional Accessories Part 2zRemovable RadiatorszPositive Pressure SystemzStainless Steel Auxiliary Wiring Cabinet NEMA 4X Hardware Base Tank Radiators TransitionsThank you!