0
You can use wattmeters to measure three-phase power. According to 'Blondel's Theorem', you can use one less wattmeter than there are conductors connecting the load to the supply. So, for a three-wire system, you can use two wattmeters but for a four-wire system, you must use three. Check out 'three wattmeter method' and 'two wattmeter method' on the internet to find the necessary connection diagrams.
Wiki User
∙ 10y ago
Wiki User
∙ 13y agothere is 2 voltages can be measured line to line voltage and phase voltage (line to neutral) where line to line voltage in case of delta connection is equal to phase coltage while in star connection line to line voltage is root 3 of phase voltage
Wiki User
∙ 12y agoYou can measure them delta (phase to phase) or star (phase to neutral). Delta voltage, in a balanced star system, is 1.732 (square root of 3) times the star voltage.
By convention, when you state a three phase voltage, unless you say otherwise, voltage is the delta voltage.
AnswerA three-phase, three-wire, system has three 'hot' (slang) conductors, termed 'line conductors' (not 'phase conductors' -although this term is widely, but incorrectly, used in the field). A three-phase, four-wire, system has three line conductors together with a 'neutral conductor'. Voltages measured between any pair of line conductors are called 'line voltages'; voltages measured between any line conductor and the neutral conductor are called 'phase voltages'.
Wiki User
∙ 12y agoUp to 200 amps, three phase distributions are measured with just one meter. All three phases are taken through the meter. It is known as a seven jaw meter base. Higher amperage distribution's use CTs (current Transformers) and PTs (potential transformers) to take samples of the power and record it on the standard seven jaw meter base.
AnswerThe 'one wattmeter method' is a method for measuring power, in watts, which only applies to a balanced three-phase load, which is star (wye) connected, and where the load's star, or neutral, point is accessible.
The wattmeter's current coil is inserted into any one of the three line conductors, and its voltage (potential) coil is connected between that line and the star point of the load.
The wattmeter reading then indicates the power per phase. So, the total power of the load is equal to three times the value indicated by the wattmeter.
If you wish to measure the power of a balanced or unbalanced, star- or delta-connected load, then it can be achieved using the 'two wattmeter method', in which the sum of the two wattmeter readings will give the total power of the load -providing there are only three wires supplying the load (see 'Blondel's Theorem').
Wiki User
∙ 11y agopower = I * E * cos(theta)
AnswerFor three-phase balanced loads, delta or wye, you must use the following equation:
P = 1.732 EL I L cos phi
where: EL = line voltage, IL = line current, phi = phase angle.
For unbalanced loads, you have to determine the power of each phase (P = EP IP cos phi), and add them up. Where EP and IP represent the phase voltages and currents.
Wiki User
∙ 9y agoThe three wattmeters each have a current coil in series with one of the live wires. The three voltage coils each have one end connected to a live wire, and the other ends connected together. The common point is usually connected to the neutral but it doesn't have to be The common point can be connected to one of the live wires, in which one of the wattmeters it will always read zero power, so it can be thrown out and the readings of the other two wattmeters can be added up to give the total power.
Wiki User
∙ 14y agoElectrical load is measured in amps. You measure each single conductor with an ammeter.
Add your answer:
Earn +20 pts
Where are three phase transformer systems used?
Any where that a three phase supply distribution is needed to operate three phase equipment.
Is a three phase three wire system safe?
Three-wire transmission is used on balanced three-phase systems when the current is known to be equal in all three phases, for example when supplying a three-phase motor. A fourth neutral wire is used when the system is liable to have unequal currents or when multiple single-phase supplies are connected to it.
What is phase voltage and line voltage in star connection?
The conductors that connect a three-phase supply to its load are called 'line conductors' or, more simply, 'lines'. The individual generator stator windings, transformer winding, or loads are called 'phases'. Lines and line terminals are identified by colours, letters, numbers, or combinations of letters and numbers. For example, A-B-C. Phases are identified by using the letters assigned to the line terminals between which the phases are connected, e.g A-B, B-C, and C-A. Voltages measured between lines ('line-to-line') are termed 'line voltages', and currents that pass through the lines are called 'line currents'. Voltages measured across a generator's windings, transformer windings, or individual loads, are called 'phase voltages', and the currents that pass through these are called 'phase currents'. For a three-phase, three-wire, system, the phase- and line-voltages are numerically-equal to each other. For a three-phase, four-wire, system, the line voltage is 1.732 times larger than the phase voltage.
What is the volts per phase on a 480 3 phase system?
The (ideal) voltage is 480V line to line. The line to neutral voltage (if it is a grounded system - 4 wires) is 480 / 1.732 = 277 volts. The actual measured voltage may be slightly higher or lower than this.
Can you run a 570 volt motor on 480 volt three phase power supply?
No, the voltage difference is too much. A 570 volt motor falls in the 600 volt range which is separate from the 480 volt range of three phase systems.
How to convert 166 amp three phase to single value?
You can't. Currents in three-phase systems are measured in each of the individual line conductors.
Where are three phase transformer systems used?
Any where that a three phase supply distribution is needed to operate three phase equipment.
How you convert the value of single phase power to value of 3 phase power?
Electric power is measured in watts. It does not matter if it is single phase or three phase. All things being equal, for the same load, the power measured in a single phase circuit or a three phase circuit, will be the same.
How do you connect 380V motor on three phase line 110V?
There are no three phase 120 volt systems.
You have 230v 3 phase power can you plug a 230v single phase motor into it?
Any two legs of a three phase system are classed as single phase. So yes a single phase motor will operate when connected. Be sure to use the proper motor protection devices to control the motor.
What are the applications of three phase to single phase electric power distribution systems?
All high-voltage distribution systems are three-phase. Single-phase 'spurs' off the main line, supplying, for example, farm houses, are simply two lines of a three-phase system.
What is phase supply and three phase supply?
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.
What are the advantages of three phase to two phase electric power distribution systems?
Polyphase systems are used because they allow the efficient transmission of electric power, in terms of power transmitted per kilogram of wire. Polyphase systems with more than three phases are very uncommon.
Why 3 phase not 4 phase or 5 phase or 6 phase?
4, 5, or 6 phase systems would cost more than three phase systems in terms of volume of copper required without offering any significant advantages.
What is arcing ground?
Arcing Grounds is a phenomenon which is observed in ungrounded three phase systems. In ungrounded three phase systems operating in a healthy balanced conditions, capacitances are formed between the conductors and ground. The voltage across these capacitances is the phase voltage
Which has the higher voltage - phase or line?
In a three phase three wire system, the phase voltage and line voltage are one in the same just different terminology. In a three phase four wire system, the line voltage is higher than the line to ground voltage. Line to ground is, line voltage divided by 1.73 (square root of three). For example 480volts /1.73 = 277 volts.AnswerIt depends upon the configuration of the three-phase system. For a delta (or mesh) connected 3-wire supply system, the line voltage is exactly the same as the phase voltage. For a wye (or star) connected 4-wire supply system, the line voltage is 1.732 (the square-root of 3) times the phase voltage.By way of explanation, for both wye and delta systems, phase voltages are measured across the windings of a three-phase transformer or across individual loads, whereas line voltages are measured between lines. For a wye-connected system, phase voltages can also be measured between any line and neutral.
How do you calculate 440v phase?
Let's get the terminology correct. A 'phase voltage' is measured across a phase, whereas a line voltage is measured between two lines. So there is no such thing as a 'phase to phase' voltage -it's a line to line voltage (hence the term 'line voltage').
