Difference Between Delta and Wye (With Table)

The terms delta and wye can be found in the field of electrical power distribution, and specifically, these terms belong to the three-phase system. Delta and wye are different types of configurations present within the three-phase system.

Delta vs Wye

The main difference between delta and wye connections is that the former is a system consisting of four wires, three of which are in triangular connections, and has no neutral wire. At the same time, the latter is joined in a star connection, with a neutral cable.

Delta connection systems have four wires in total. It has three phases connected in the form of a triangle. There is no neutral cable, but there is one ground wire. Here, the phase voltage is equal to the line voltage.

Wye connection system has a total of five wires, out of which three hot wires are connected to a neutral wire. Wye system utilizes a star connection. Here, the phase voltage is equivalent to the line voltage divided by the root of 3.


 

Comparison Table Between Delta and Wye (in Tabular Form)

Parameters of comparison

Delta

Wye

Number of wires

The total number of wires in a delta connection system is four, with three wires connected to one ground cable.

The total number of wires in a wye connection system is five, with three hot wires connected to a single neutral wire.

Neutral cable

Delta connection system does not include the use of a neutral cable.

Wye connection system does include the use of a neutral cable.

Shape of connection

A delta system is connected in a triangular shape configuration.

A wye system is connected in a “Y” shape, or configured in a star shape.

Phase voltage

In a delta system configuration, the phase voltage is equal to the line voltage.

In a wye system configuration, the phase voltage is equivalent to the line voltage divided by the root of 3.

Phase load

In the delta system, the phase load or single-phase loads is seen to pass through only one wire/phase.

In the wye system, the phase load or single-phase loads is seen to pass-through all wires.

Cost of installation

The delta system can be costlier to install in comparison to wye system.

The wye system is cheaper in terms of maintenance and installation.

 

What is Delta?

The delta configuration is part of the three-phase system (in the field of electrical power distribution). Here, the configuration mainly focuses on how the wires are arranged and connected to provide lower phase voltage.

In the delta configuration, we see that the total number of wires involved is four, with three of these wires connected to one ground wire. In delta systems, there is also no neutral wire required. One thing to also note about delta configured cables is that they are connected in a triangular shape. This triangular arrangement of wires is also referred to as mesh connection.

In a delta system configuration, the phase voltage is equal to the line voltage, and is depicted as shown below –

Phase voltage (Vp) = Line Voltage (VL)

Also, one primary factor in delta systems is that the phase load or single-phase loads is seen to pass through only one wire/phase.

Overall, in terms of maintenance and installation, delta system connections are costlier in comparison to wye systems.

 

What is Wye?

The wye system is one of the two different types of configurations of the three-phase system (in the field of electrical power distribution). The wye configuration has better helped reduce phase voltage required in a system. In the wye system, we observe a total number of five wires, with three hot wires connected to neutral cable wire.

In a wye system, the wires are connected in the form of a “Y”, hence why the name of the system is “wye”. Also, the cables can be combined in the form of a “star”.

In a wye system configuration, the phase voltage is equivalent to the line voltage divided by the root of 3 (1.732), and is depicted as shown below –

Phase voltage (Vp) = Line Voltage (VL)  / 1.732

In the wye system configuration, the phase load or single-phase loads is seen to pass-through all wires. The wye system is also cheaper in terms of installation and maintenance as compared to the delta connection in the three-phase system.


Main Differences Between Delta and Wye

  1. In a delta connection system, there are four wires, with three wires connected to one ground cable., while in wye system there are total of five wires.
  2. In the delta system configuration, there is no neutral cable involved in the connection, while in the wye system, there is a neutral cable required.
  3. Delta system is less expensive in terms of maintenance, installation, and purchase of wires, in comparison to the wye system configuration.
  4. In a delta system configuration, the phase voltage is equal to the line voltage, while in a wye system, the phase load or single-phase loads is seen to pass-through all wires.
  5. A delta system is connected in a triangular shape configuration, while a wye system is connected in a “Y” shape, or configured in a star shape.

 

Conclusion

The two types of configurations present in the three-phase system are the delta and wye systems. These systems come under the field of electrical power distribution and are needed when calculating phase and line voltage. The delta system is connected in the shape of a triangle, and this type of connection is also referred to as a mesh connection.

The wye system is connected in a star shape or “Y” shape. One thing to also note is that the delta system configuration, unlike the wye system, does not require the use of a neutral cable; hence why the number of wires needed for a delta system is four (there are five wires in a wye system configuration). The delta and wye systems have their unique way of measuring the phase voltage and the line voltage of the system.


References

  1. https://ieeexplore.ieee.org/abstract/document/5677478/
  2. https://digital-library.theiet.org/content/journals/10.1049/ip-c.1992.0035