'Bundled' conductors describe a line in which two or more conductors are supported from the same insulator chain. In the UK, 275-kV transmission lines typically use two conductors per line, and 400-kV transmission lines typically use four conductors per line. The purpose of bundling conductors is to spread the electric stress on the conductors (e.g. for four conductors, the same amount of electric flux will be 'shared' between the four conductors, rather than concentrated on the surface of one conductor).
Using a distribution system (e.g. 11 kV in the UK) as an example, the primary of a three-phase distribution transformer is delta-connected, which requires to be supplied by three line conductors. So a neutral conductor is superfluous.
There is no such thing as a 'phase conductor'. The correct term is 'line conductor'. Line conductors are the three energised conductors that supply a three-phase load.
3 phase cable is transposed to minimize the effect of leakage/capacitance current.
r1 plus r2 is the measurement of the combined electrical continuity of the phase conductor and circuit protective conductor on and electrical circuit.
Air-blast circuit breakers are used to disconnect high-voltage transmission or distribution circuits in the event of a fault. One circuit breaker is required for each of the three line conductors; there is not normally a neutral conductor in high-voltage three-phase transmission/distribution lines.
It depends on the electrical standards of the country in which you live. In Europe, for example, the line conductor(not 'phase conductor'!) is brown, the neutral conductor is blue, and the earth conductor* is green/yellow stripe.[*properly called a 'protective conductor']
There is no such thing as a 'phase conductor'; the correct term is 'line conductor'. In a single-phase system, the line conductor is the energised conductor; in a three-phase system, there are three (energised) line conductors.
Using a distribution system (e.g. 11 kV in the UK) as an example, the primary of a three-phase distribution transformer is delta-connected, which requires to be supplied by three line conductors. So a neutral conductor is superfluous.
No neutral is necessary, because the transmission line's line currents are roughly balanced and, so, the phasor sum of those currents will be relatively insignificant, rendering the need for a neutral conductor to be an unnecessary expense. In practise, for most transmission towers, each of the three 'lines' comprises not just a single conductor but, rather, a number of conductors which are bundled together in order to reduce electric stress surrounding the line. The number of conductors per bundle increases with transmission voltages. In the UK, for example, 400-kV transmission lines normally comprise bundles of four conductors, whereas 275-kV transmission lines normally comprise bundles of two, and 132-kV lines just one. Running along the top of transmission towers is an earthed conductor, called a 'guard conductor', whose function is to protect the lines from lightning strikes during electrical storms. Many transmission towers also have two, separate, three-phase circuits -one circuit on each side of the tower. But, definitely, no neutral!
There is no such thing as a 'phase conductor'. The correct term is 'line conductor'. Line conductors are the three energised conductors that supply a three-phase load.
A single phase supply can be obtained between any pair of line conductors or between a line conductor and a neutral conductor.
Yes, except that the correct term is 'line' conductor, not a 'phase' conductor.
All a.c. transmission systems are three-phase systems, which comprise three line conductors which are suspended from towers. Each 'line' is generally made up of a number of 'bundled' conductors -according to the transmission voltage- to reduce the electrical stress. Many transmission towers carry two separate three-phase circuits, one on each side of the tower.
well that all depends when your dealing with what voltage is being applied to your motor,home, or building. the phase conductor in A panel box can be labeled with either red, or blue tape meaning that's the phase conductor or hot. This all comes down to with what type of electrical equipment or service your working with, The word phase just means that's the hot side and the hot side is usually the black wire, although a red or blue wire can to. Plus a wire being the hot conductor, or load the NEC likes to call it the phase conductor.CommentThe term 'phase' conductor, in this context, is incorrect. The correct term is 'line' conductor.
High voltage transmission lines can transmit more power when the total impedance of the line is lowered. Inductive reactance is typically ten times larger than the series resistance of a conductor. Bundling drastically decreases the reactance of the largest component of impedance, the reactive inductance, and adding a second conductor also cuts real energy losses by one half because the resistance is reduced by one half. I squared X losses are reduced which means that the voltage drop along the line is reduced.AnswerThere is a limit to how much electric field intensity an individual conductor can withstand. This is greatest at the surface of the conductor. Even in dry air, ionisation may result causing corona discharge to take place, and may lead to a breakdown in insulation where the conductor is supported from its tower.Transmission line conductors, therefore, are bundled in order to reduce the electric field intensity which would be excessive if a single conductor were to be used instead. With bundled conductors, the same field is distributed equally between the bundled conductors, reducing the field intensity per conductor.
A ground, or earth, conductor is never included in the conductor count. So, a three-phase, three-wire, system has three line conductors, whereas a three-phase, four-wire system, has three line conductors and a neutral conductor.
I think you mean 'single-phase supply', rather than 'phase supply'. All high-voltage a.c. transmission and distribution systems are three-phase systems. This is because, for a given load, a three-phase system uses less copper than a single-phase system. Three-phase generators produce three 'phase voltages', each displaced, by 120 electrical degrees. These voltages are produced in three windings which are electrically connected in what is called a 'delta' configuration, with each 'corner' of the delta connected to the transmission system by 'line' conductors. Three-phase systems are either 'three-wire' or 'four-wire' systems. Generally, three-phase, three-wire, systems are used for high-voltage transmission and distribution, whereas three-phase, four-wire, systems are typically (but not always) used for low-voltage distribution. Three-wire systems comprise three conductors called 'line conductors'; four-wire systems comprise three 'line conductors' and a 'neutral conductor'. Depending the voltage standards used in the country in which you live, a single-phase supply is obtained either by connecting single-phase load between any two line conductors, or between any one line conductor and the neutral conductor.