PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase...
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Transcript of PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase...
![Page 1: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/1.jpg)
PowerPoint® Presentation
Chapter 4Transformer Connections
Voltage Transformation Three-Phase Circuits
Delta Connections Wye Connections
Delta-to-Wye Connections Wye-to-Wye
Connections Wye-to-Delta Connections
Delta-to-Delta Connections Open Delta
Connections Delta Connection with High Leg to Ground Three-Phase Transformer Polarity
![Page 2: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/2.jpg)
Chapter 4Transformer Connections
The low‑voltage winding of a standard distribution transformer connected to a single-phase circuit is normally made with two equal coils. These sections are arranged so that they may be connected in series or parallel.
![Page 3: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/3.jpg)
Chapter 4Transformer Connections
Transformer polarity may be subtractive or additive.
![Page 4: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/4.jpg)
Chapter 4Transformer Connections
The polarity of a transformer may be determined using a known transformer or with AC voltage.
![Page 5: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/5.jpg)
Chapter 4Transformer Connections
A delta connection has the wires from the ends of each coil connected end-to-end to form a closed loop.
![Page 6: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/6.jpg)
Chapter 4Transformer Connections
Studying the current in a delta-connected system at both 0° and 90° illustrates the current flow in a delta-connected system.
![Page 7: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/7.jpg)
Chapter 4Transformer Connections
A wye connection has one end of each coil connected together and the other end of each coil left open for external connections.
![Page 8: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/8.jpg)
Chapter 4Transformer Connections
Studying the current in a wye-connected system at both 0° and 90° illustrates the current flow in a wye-connected system.
![Page 9: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/9.jpg)
Chapter 4Transformer Connections
A 3-phase delta-to-wye connection is often used for distribution where a four-wire secondary distribution circuit is required.
![Page 10: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/10.jpg)
Chapter 4Transformer Connections
Three single-phase transformers may be connected in a wye-to-wye connection to form a 3-phase transformer.
![Page 11: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/11.jpg)
Chapter 4Transformer Connections
A wye-to-delta connection permits single-phase and 3-phase loads to be drawn simultaneously from the delta-connected secondary at the same voltage.
![Page 12: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/12.jpg)
Chapter 4Transformer Connections
In a wye-to-delta connection of three single-phase transformers, one unit may be disconnected from the circuit and service maintained with the secondary operating in open delta connection at 57.7% of normal bank capacity.
![Page 13: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/13.jpg)
Chapter 4Transformer Connections
In a delta-to-delta connection, the voltage of each transformer is equal to the 3-phase line voltage and the current in each of the transformers is only 57.7% of the line current.
![Page 14: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/14.jpg)
Chapter 4Transformer Connections
Grounding one of the midpoints of the windings provides 240 V/120 V, single-phase, 3-wire service for lighting applications.
![Page 15: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/15.jpg)
Chapter 4Transformer Connections
An open delta connection makes 3-phase power available anywhere along the distribution line with the use of only two transformers rather than the usual three.
![Page 16: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/16.jpg)
Chapter 4Transformer Connections
A delta connection with a high leg to ground provides 240 V, 3-phase power to equipment and 120 V power for lighting and receptacles.
![Page 17: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/17.jpg)
Chapter 4Transformer Connections
The phase sequence on the secondary of a three-phase transformer is the same as the phase sequence on the primary.
![Page 18: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/18.jpg)
Chapter 4Transformer Connections
Transformers are classified into connection groups according to their phase shift.
![Page 19: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/19.jpg)
Chapter 4Transformer Connections
![Page 20: PowerPoint ® Presentation Chapter 4 Transformer Connections Voltage Transformation Three-Phase Circuits Delta Connections Wye Connections Delta-to-Wye.](https://reader034.fdocuments.us/reader034/viewer/2022050703/5517f7e7550346a2228b48d8/html5/thumbnails/20.jpg)
Chapter 4Transformer Connections