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Because neutral doesn't have to carry the load current .This is either used for unbalanced current (in Y-connection) or for earthing purpose which don't require high ampere rating....

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Q: Why half size of neutral conductor in 3.5 core cable?
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Why would you get half voltage between live and neutral?

You can measure a small voltage between earth and neutral, even if the neutral is grounded to earth, because the neutral conductor acts as an antenna picking up electromagnetic radiation in the atmosphere. -------------------------- If the above answer were true, the earth conductor would also act as an antenna. But the real answer is, if you read ANY voltage between the neutral and earth, the neutral is broken somewhere between where you are measuring and the panel or not properly bonded in the panel. Call a competent electrician to repair the problem.


Why neutral cross section is half the phase in three phase cable while it has to carry current of summation of all phase..?

The current carried by the neutral of a three phase four wire system is the un balanced current. If the three phase system was completely balanced on all three phases there would be no need for a neutral, eg a three phase motor. This neutral current will be less that the phase current so a reduction in the neutral size is allowed.


State the appropriate portion of water and land in the earth surface?

the apropiate amount is half the core area


Ground wire share?

That's not much of a question but I think you mean "how or why do you share a neutral?" A neutral is sometimes called a "grounded conductor" because it is connected to the main ground at the point of entry of a home or building. But it is not the "ground". You typically have 4 main conductors at the point of entry of your home or other building. 2 are "hot" wires, 1 is the neutral(these three come from the utility provider) the last one is the ground wire(s) usually coming from ground rods pounded into the earth outside (sometimes there is also a conductor connected to the copper water pipe where it comes into the home or to a rebar encased in the concrete foundation of the building)(these are all considered the "grounding electrode conductor" or ground) the neutral and ground are connected at one point only usually in your panel but sometimes in the meter-base. there is approx. 240 volts potential between the two "hot" wires. Both wires are approx. 120 volts each to the neutral. each "hot" wire is also known as a "phase". If you could see the electrical panel with no breakers in it you would notice that one "hot" wire (or phase) feeds half of the breaker spaces and the other "hot" wire feeds the other half but the panel is not split up as it might look (left and right halves). Each phase feeds every other space vertically. So the top two breakers would be fed from "A phase" then the second two by "B phase" and so on down the panel. (this allows a double wide or 2-pole breaker to span both phases and feed 240 volts to your electric range or dryer). Now to your question: Due to the way Alternating Current (AC) is generated, the two phases are polar opposites of each other. When "a-phase" is at it's peak, "b-phase" is at it's lowest point. The neutral corresponding to it's phase conductor follows this pattern. As long as the two circuits are on opposite phases, those two circuits can share one neutral conductor with no overloading problems. If you share one neutral with two circuits from the same phase, you will over-load that neutral and it could create enough heat to potentially cause a fire. There is no over-load protection connected directly to the neutral. Electricians share neutrals for a few reasons. It eliminates wiring costs and also reduces the number of conductors in conduits. You will have problems if you try to share a neutral on circuits requiring GFCI or Arc Fault protection. It causes nuisance tripping and major headaches for all. Sharing neutrals has been a common practice for years. In three-phase systems(common in commercail and industrial buildings), three circuits can share one neutral as they are 120 degrees from each other.(picture a round generator of 360 degrees total).


How do you reduce volt drops in cables?

You can draw less current, half the current gives half the amount of volt drop. Or use a thicker cable because doubling the cross-section area would also give half the volt drop.

Related questions

What is 3.5 core cable?

it means 3conductors(ie RYB) and half neutral ie size of neutral would be half size of other conductors...


Difference between 2 core wire and 4 core wire?

in 4 core cable all four cables are equal dia and in a 3.5 core cable 3 cores are equal dia and fourth one will be with half dia. and it is used for neutral in 3phase 4 wire syastem


What conductor IDE cable has half the number of pins as it has wires?

80


Can we use 150 mm 3.5 4 core cable as a 150 mm 4 core cable?

Yes. remember that one core is with reduced size by half.


What is the correct size of main bonding conductors for a tn-s system having 25mm phase?

By rule of thumb, the neutral conductor is half the size of main conductor.


Why is the neutral wire in any system half the magnitude of the line wire?

in case of motor, only 3core cable are used. Because there is phase balence between the winding. But in case of wiring,panel installation, 3.5c cables are normally used. Because there is unbalenced between the phase current. So the neutral taken to give the return path to flow of unbalenced (rush) current. Which always less than phase current,so the neutral cable is take half of the phase cable.


Why you take radius or size of neutral wire half wrt phase conductor?

On three phase services over 200 amps the electrical code allows the electrical contractor to reduce the size of the neutral wire . This saves the customer money. There are conditions as to how much the neutral can be reduced but it is not as low as half the supply conductors. The reason that the neutral can be reduced is that it only carries the unbalanced current on the three phase four wire system.


Is a neutral considered a current carrying conductor?

No, in a three phase balance load, there should not be any current through Neutral conductor. If it is a 2 wire, single phase system, the Neutral will carry the same current as live conductor if the system has no Earth fault, leak.


Why would you get half voltage between live and neutral?

You can measure a small voltage between earth and neutral, even if the neutral is grounded to earth, because the neutral conductor acts as an antenna picking up electromagnetic radiation in the atmosphere. -------------------------- If the above answer were true, the earth conductor would also act as an antenna. But the real answer is, if you read ANY voltage between the neutral and earth, the neutral is broken somewhere between where you are measuring and the panel or not properly bonded in the panel. Call a competent electrician to repair the problem.


Why do you have a temporary power interruption to your alarm clock when you run the vacuum?

This is not a normal situation. The circuit could be on a three wire circuit and the neutral conductor may be loose on one half of the circuit. Get an electrician to find the cause of this problem.


Why neutral cross section is half the phase in three phase cable while it has to carry current of summation of all phase..?

The current carried by the neutral of a three phase four wire system is the un balanced current. If the three phase system was completely balanced on all three phases there would be no need for a neutral, eg a three phase motor. This neutral current will be less that the phase current so a reduction in the neutral size is allowed.


If conductor is cut half of its length will it affect its conductance?

Yes. If a uniform, homogeneous conductor is reduced to half of its length, then its conductancebecomes double, (equivalent to its resistance becoming 1/2 as great).