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(Single Phase)Transformers TransformerAtransformeris an electrical device which transfers electrical energy from one electric circuit to another without changing the frequency. Transformers either increases or decreases AC voltage.Type of Transformer

Core Type TransformerIn core type transformer, windings are cylindrical former wound, mounted on the core limbs. The cylindrical coils have different layers and each layer is insulated from each other. Materials like paper, cloth or mica can be used for insulation. Low voltage windings are placed nearer to the core, as they are easier to insulate.Shell Type TransformerThe coils are former wound and mounted in layers stacked with insulation between them. A shell type transformer may have simple rectangular form, or it may have a distributed form.

Uses of TransformersIt can rise or lower the level of Voltage or Current (whenvoltage increases,currentdecreases and vice versa becauseP(power) = V(Voltage)x I(Ampere), and Power is same)in an AC Circuit.It can increase or decrease the value of capacitor, an inductor or resistance in an ACcircuit. It can thus act as an impedance transferring device.It can be used to prevent DC from passing from one circuit tothe other.it can isolate two circuits electrically

Parts of a single phase Transformer

SINGLE PHASE Transformer

SINGLE PHASEA single-phase transformeris a type ofpower transformerthat utilizes single-phase alternating current, meaning the transformer relies on a voltage cycle that operates ina unifiedtime phase.Uses of SINGLE PHASESingle-phase transformers are often used to supply power for residential lighting, receptacle, air-conditioning, and heating needs. Single phase transformers can be made even more versatile by having both the primary winding and secondary winding made in two equal parts. (series or parallel configurations)

Primary and Secondary Winding

Primary WindingIn atransformer, thewinding is directlyconnected to the inputpower. One or moresecondarywindings provide theoutputto theloador loads. Secondary WindingIn atransformer, thewinding provides theoutput to theloador loads. There may be multiplesecondary windings, while the winding that is directlyconnectedto the inputpoweris theprimary winding.FLC(Full Load Current)Thegreatestcurrentthatacircuitorpieceofequipmentisdesignedtocarryunderspecifiedconditions.FLC is used when you size breaker size and wire size for motors.K KiloV VoltsA AmpereW Watt is a measurement of real powerFLC Chart

Connections of Transformers(Single Phase)

Buck And Boost Transformer

Buck-Boost TransformersBuck-Boost transformers are small, single phase, dry type distribution transformers designed and shipped as insulating/isolating transformers. They have a dual voltage primary and a dual voltage secondary.Buck-Boost TransformersA buck-boost transformer is classified as an autotransformer. A buck-boost transformer provides a means of rising (boosting) or lowering (bucking) a supply line voltage by a small amount (usually no more than 20 percent).The most common example is boosting from 208 volts to 230 volts, usually to operate a 230 volt motor such as an air-conditioner compressor, from a 208 volt supply line.Advantages of Buck-boost transformerslow costcompact sizelight weight more efficientversatile, many applications5-10 times increase in KVA Disadvantage of Buck-boost transformersNo circuit isolationCannot create a neutralKVA and voltages do not match on the nameplate

Buck and Boost Ratings

Single-phase connection diagrams for buck or boost transformers connected as autotransformers to change 240 volts single-phase to 208 volts and vice versa.

Operation on a Single Phase Transformer1. As soon as the primary winding is connected to the single phase as supply, an ac currentstarts flowing through it.

2. The ac primary current produces an alternating flux in the core.

3. Most of this changing flux gets linked with the secondary winding through the core.

4. The varying flux will induce voltage into the secondary winding according to the Faradayslaws of electromagnetic induction.

Vacuum Pressure

Vacuum PressureUsed to control the amountof positive and negativepressure a transformertank has on it.MaintenanceYearly check the transformerCheck vacuum pressure gauge for pressure readingCheck oil levelCheck temperature maximum and minimumCheck for leaksCheck paint conditionCheck transformer top and radiators for foreign materialCheck radiator conditionCheck fans and cooling systems