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Yes, this is done on star (wye) systems where one neutral is used for three phase wires. e.g. 120/208 voltage system.
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What is an electric shared neutral?
An electric shared neutral is the white or negative wire that is shared between two electrical circuits on a basic single phase system. Most electrical devices use 120 volts and require a "hot" wire and a neutral wire to operate. Some larger devices use 240 volts and require two "hot" wires to operate. Two circuit breakers in an electrical panel can share one neutral wire as long as the breakers are not on the same "leg" of power. When looking at an electrical panel there are usually two "legs" of power feeding all the breakers, each leg has 120 Volts to ground, if the "legs" are combined you will have 240 Volts. A neutral wire can be shared by two circuits as long as the breakers are on separate "legs". If someone needed to add two circuits in their home, the could run what is called a 3-wire romex, It has a black wire, a red wire, a white wire and a ground wire. The white wire is the neutral for both the black and red 120 volt circuits, and the breakers for the new circuits would need to be on separate "legs" in the panel.
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).
Do you have to pin breakers together when sharing the neutral on branch circuits?
Pinning breakers is becoming a thing of the past. This is due to the manufacturing of two pole breakers with one common trip reset handle. The electrical code states that on a 240 volt breaker if one leg trips the other leg must be disconnected from the supply also. This is a safety factor so that if they weren't tied together and one leg tripped the other half of the breaker would remain "hot". Any one working on that circuit in the tripped position could get a nasty shock from the un-tripped leg. Pinning the breakers on 240 volts was done because it was convenient to use single pole breakers in the distribution panel. To abide by the code the two single pole breakers were common tied together. When the branch circuits share a neutral to a common box they have to be common tied for the same reason above. This type of circuit is found on kitchen counter receptacles. Two separate circuits that share a neutral and go to separate junction boxes do not need the breakers tied.
Any problems with shared neutral for for 4 15 amp breakers each on dedicated circuits?
Yes. If it a residential home then you can only have two breakers per neutral and they need to be on opposite legs of your panel. If it is a commercial 3phase panel then you can only put 3 breakers on a shared neutral. Here's why. In your panel assuming its residential you have two power wires and one neutral and these power wires are called legs. If you attach two breakers on the same leg that is across from each other on opposite sides of the panel or skipping a space between breakers on the same side at 15A apiece you return on the neutral will not be balanced and you will have the possibility of 30A coming back to your panel on the neutral which will fry a 14 Awg or even 12 Awg for that matter and cause a fire. Now if the breakers are in tandem that is they have the breaker tie that connects two breakers together they will be on separate legs and then only will your breakers/circuits be balanced and it will be safe to share a neutral on. If two tandem breakers are connected to a single neutral and they are all 15A breakers your return would be 30A again because although your tandem breakers are balanced now you have two tandem breakers returning a potential 15A per two breakers and that adds up to 30A. The next problem you have is when you share a neutral as per the National Electric Code if one breaker trips the other breaker also sharing that neutral must trip so that when the power is off any current that could possibly return through the neutral wire will be cut off. So now this creates another problem with 4 breakers sharing the same neutral is now there is no way to get all four to trip at the same time if there was a ground fault (a short) or an overload. and someone could get nailed by any current coming back on the shared neutral. All the same applies for 3phase except there are 3 power wires and you can use 3 breakers with a 3 breaker tie instead of just two. You either need to run one neutral per tandem breaker or four neutrals for four circuits/breakers. Tandem breakers controlling two separate circuits are a pain because when one breaker trips they trip the other circuit also. Tandems are mostly used for two circuits going to the same appliance so that no power on either leg reaches the appliance when it needs to be off.
What is one half breaker scheme used for 400220kv substation?
a method of interconnecting several circuits and breakers in a switchyard so that three circuit breakers can provide dual switching to each of two circuits by having the circuits share one of the breakers, thus a breaker and one-half per circuit; this scheme provides reliability and operating flexibility, and is generally used at 500 kV when more than five lines terminate in a substation.
Can one neutral share two phases?
Yes, they can share a neutral
How many neutrals for three-phase multi circiuts?
For a three phase distribution system there is one neutral. In North America the electrical code allows three individual branch circuits to connect with one neutral as long as the three circuits each use an individual phase leg. This differs from 120/240 volt single phase wiring where only two legs can be used with one neutral.
Can you use a GFCI on an unswitched circuit line red that uses the same neutral white for a switched circuit coming from the other phase line black in a 240v breaker panel?
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.
How many electrons in oxygen family gain or share?
fluorine in its neutral state (meaning it isn't an ion) typically gains one electron
How is it wired or terminated to a phase if all circuits are on the same phase or hot legit would be limited to one neutral?
The question makes no sense.
What is an electric shared neutral?
An electric shared neutral is the white or negative wire that is shared between two electrical circuits on a basic single phase system. Most electrical devices use 120 volts and require a "hot" wire and a neutral wire to operate. Some larger devices use 240 volts and require two "hot" wires to operate. Two circuit breakers in an electrical panel can share one neutral wire as long as the breakers are not on the same "leg" of power. When looking at an electrical panel there are usually two "legs" of power feeding all the breakers, each leg has 120 Volts to ground, if the "legs" are combined you will have 240 Volts. A neutral wire can be shared by two circuits as long as the breakers are on separate "legs". If someone needed to add two circuits in their home, the could run what is called a 3-wire romex, It has a black wire, a red wire, a white wire and a ground wire. The white wire is the neutral for both the black and red 120 volt circuits, and the breakers for the new circuits would need to be on separate "legs" in the panel.
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).
Do you have to pin breakers together when sharing the neutral on branch circuits?
Pinning breakers is becoming a thing of the past. This is due to the manufacturing of two pole breakers with one common trip reset handle. The electrical code states that on a 240 volt breaker if one leg trips the other leg must be disconnected from the supply also. This is a safety factor so that if they weren't tied together and one leg tripped the other half of the breaker would remain "hot". Any one working on that circuit in the tripped position could get a nasty shock from the un-tripped leg. Pinning the breakers on 240 volts was done because it was convenient to use single pole breakers in the distribution panel. To abide by the code the two single pole breakers were common tied together. When the branch circuits share a neutral to a common box they have to be common tied for the same reason above. This type of circuit is found on kitchen counter receptacles. Two separate circuits that share a neutral and go to separate junction boxes do not need the breakers tied.
Is a 3 phase cable one circuit?
If it is powering a single 3 phase device and is protected by a single throw 3 pole breaker or disconnect, yes. If all three hots share one neutral, and supply different devices or circuits, breakers should be able to trip independently but would still have to disconnect all three phases together.
Can 2 220 circuits share one ground?
Yes they should, since there is only one earth, no seriously all earths in a ac system should be joined together.
Where can one purchase flexible printed circuits?
Flexible printed circuits are used for assembling electronic circuits. You can purchase these from many companies such as Flexible Circuit, All Flex Inc and Strataflex.
What are the benefit for middle phase earthing of a voltage transformer?
This is probably a question about split-phase systems where the transformer secondary is 240 v with an earthed centre-tap forming the neutral. The system transmits power on three wires, which are two lives and a neutral. Each live wire has 120 v to neutral and 240 v to the other live wire. Thus two 120 v low-power circuits and one 240 v high-power circuit can be supplied. With balanced currents in the two 120 v circuits, the current in the neutral is zero and this results in zero lost power in the neutral.
