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Why is the neutral wire thinner in overhead 3-phase AC transmission line?
Wiki User
∙ 11y ago
A smaller neutral wire in a three phase system can be used because it does not carry the full line current. It carries the unbalanced current of all three leg loads. This is one reason that three phase loads on a distribution panel should be equalized as much as possible to reduce the current on the neutral.
Wiki User
∙ 13y ago
Wiki User
∙ 11y agoActually if the 3 phase system is balanced, i.e. the loads are distributed evenly on three phases, there will be zero current on neutral. For that the neutral wire is thin because it is not expected to carry high current
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You switched leads on your 3phase motor and it did not reverse?
Then it is not a three phase motor.
How many amps does a 10kw heater draw that's 3phase 220volt?
40 amps
How do you wire a 1 to 3 phase roto verter?
How do u wire a 1 to 3phase rotoverter
Furnance rating 380v 3phase 15kva how much current amps takes?
Pls.answer me of above question
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.
How much will neutral current be in a 3phase 4-wire y system with a balanced load?
Balanced load means no unbalanced currents, so the neutral current should be near zero.
Why 3phase line used in transmission?
owing to its advantages of carrying large amount of power compared to the remaining systems .. 3 ph is widely used.
Will the fifth harmonics will flow into neutral line in a 3phase balanced system?
for a balanced system ? no, cause 5th harmonics has purely negative sequence in balanced system, only zero sequences can flow. Unless the system is unbalanced, then only the 5th harmonics zero sequence component will flow in the neutral.
Which starter is best for 7.5 hp 3phase motor?
Which starter is best for 7.5 hp 3phase motor?Read more: Which_starter_is_best_for_7.5_hp_3phase_motor
Why do we use 1.73 as multiplication factor to calculate Phase to Neutral voltage?
because 3Phase power - V X I X Cos Phi X Square root of 3 and square root of 3 - 1.73
What is the angle between 3phase?
120 degrees
How to run a 3phase seperator 1440?
To run a 3phase separator in 1440 depends on the fluid type and the flowing conditions. It is then controlled by pressure and the fluid levels that in the vessel.
How do you convert 3phase 1hp motor into units?
Into units of what?
You get high voltage and burn your appliances due to neutral failure?
It would happen in case of 3phase domestic use where consumer side load balancing is not being done and there is loose connection in the neutral wire. Due to the unbalance and poor neutral, the system neutral will be shifted and un balanced voltages will be recorded in all the 3 phases of the house. The phase loaded with much utilities will indicate less voltage and other will have high voltage. Gadgets connected to this phase will be damaged.
What is the Max amp rating for 3phase dc motor?
the three phase dc motor never seen yet motor eaither 3phase m/r or dc motor.
What is the rated current for 3phase 50 hp 460v?
60.4
Why 3phase 4 wire system neutral current is zero when balanced load conditionwhere same current flow through the phase and neutral also?
Because the voltage in the three live wires is 'phased' by one third of a cycle, or 120 degrees, and if the three currents have equal amplitude they add up to zero in the neutral. When one line peaks at +1 amp, let's say, the other two are both at -0.5 amps and there is nothing in the neutral. That state of affairs remains the same at all parts of the AC cycle.
