Neutral will be closest to protective earth ground. In the US, neutral is white.
we can check using tester ,when tester is connected to phase only lamp of the tester glows and when it is connected to the nuetral the lamp does not glow.
another method is, connect the voltmeter to any one of the terminal and ground if the voltmeter shows 110v 0r 220v then it is phase and the other is nuetral.
A phase leg connects to the neutral through the connected load.
Question is incorrect. in a 240 Volt single phase circuit, how can you have A phase and B phase?
yes we can use as a single phase circuit because at practise directly the 3-phase circuit is made by combining the three single phase circuits
If the test shows that there is a continuity between the phase leg and the neutral with no load connected, then that circuit should not be energized. If the circuit was energized then the fuse or breaker protecting that leg will trip the circuit open.
It does not matter what line in (the phase or neutral) is the fuse. In a closed series circuit current in all areas of the circuit is equal. It's best to put the fuses in both wires (phase and neutral) and even better for each individual device in the chain.
A fuse is an overcurrent protection device, which protects a circuit by melting in the event of either a sustained overload current, or a short-circuit current. A short-circuit current will occur when a line (not 'phase') conductor makes direct contact with a neutral (or earth) conductor.
The neutral provides a path back to the source for the electricity. In a three-phase circuit, it is mainly used to carry the unbalanced load back to the source. In theory, a perfectly-balanced three-phase circuit would not need a neutral, but this is almost impossible to achieve in actual practice.
There is more current flowing and the wire can not flow that much current.
Circuit is complet 1 phase,2 neutral...& groung is use for ignor e/f,current leakage.
Yes. You are allowed to use a neutral for one circuit from each phase of your service. For example, in a residential service, you can use the same neutral for circuits 1 and 3. In a commercial (3 phase) service, you can use a neutral for circuits 1, 3, and 5. You will experience problems if you use a neutral for two 'black' circuits or two 'red' circuits, if the circuits originate from the same phase bus bar. Also, AFCI's are sensitive to sharing neutrals, but GFCI's are not.
The current is the same in the three live wires. The voltage can be described as the line voltage (phase to neutral) or the phase voltage (phase to phase) which is larger by a factor of sqrt(3). So a line voltage of 230 v corresponds to a phase voltage of 400 v.
In a single-phase circuit like a house fed from 4-wire three phase in the street, the current flows in the live and neutral wires. The neutral currents from a street of houses are expected to cancel each other so that the overall current in the neutral leaving the transformer is small.