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What is nominal line voltage?
'Nominal' means 'named'. So a 'nominal' voltage is the named voltage of a system. For example, when we talk about a 120-V or 240-V system, we are describing their nominal values, not their actual values which can change from moment to moment.
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Overexcited Transformer. Operation above the rated supply voltage causes the ferromagnetic core to enter saturation; this means that the primary inductance is reduced and s…ince the primary current is limited by primary resistance +inductance then the primary current will increase and possibly cause the primary winding current capacity to be exceeded. Also the iron core hysteresis loss will likely increase and cause the core temperature to rise. We have not considered eddy currents in the core, probably these are less than the hysteresis core loss. Addition: also the stresses that caused by increasing the voltage will over heat the transformer by mean the life time is redused, for example: if the life time for a transformer is 20 years this number will decrease due to operating the transformer on a higher voltages than the rated...
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 w…inding, 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.
The word nominal means the lowest possible safe amount. So, nominal current or nominal voltage is the lowest amount necessary to perform an electrical function like keepin…g a light turned on. Answer The original answer is incorrect. 'Nominal' simply means 'named'. So a 'nominal voltage' is the 'named voltage', as opposed to an 'actual voltage'. For example, the nominal voltage of residential supplies in the UK is 230 V; however, this value is allowed to vary between +10/-6% of the nominal voltage. In other words, a nominal voltage of 230 V may vary between 216 V and 253 V.
Different countries have different legal limits to how much their electricity supply voltages may vary. In the UK, for example, the nominal supply voltage for residential supp…lies is 230 V, but this is allowed to vary between -6% and +10%. So, as you can see, and 'actual' voltage of 250 V is within the allowable upper limit (253 V) for the nominal voltage of 230 V. So, to answer your question, you need to check what the allowable variation is at your location (your electricity supplier can confirm this) -I would guess that 250 V would be well within the allowance for 240 V.
It is the rated voltage of an electric equipment. It is the voltage at which the device is designed to operate. Another Answer Nominal means 'named'. So a nominal voltage is …the 'named' voltage. For example, the nominal voltage of the supply system in Britain is 230 V. But its actual value is allowed to vary between 216.2 V and 253.0 V.
The three 'hot' conductors supplying a three-phase system are called 'line conductors'. A line voltage is the voltage between any pair of line conductors. In a 'delta' conne…cted system, phases are the loads connected between the three line conductors. So, for a delta-connected load, the phase voltages correspond to the line voltages. In a 'star' or 'wye' connected system, phases are the loads connected between the line conductors and a neutral conductor. So for a star-connected system, the phase voltages exist between any line conductor and the neutral conductor, and equate to 0.577 x the value of a line voltage (or, if you prefer, a line voltage is 1.732 x a phase voltage). To summarise, for delta connected systems, a line voltage is measured between line conductors, and a phase voltage is numerically equal to that line voltage. For star-connected systems, line voltages exist between line conductors, whereas phase voltages exist between any line conductor and a neutral conductor.
Nominal voltage is the 'named' voltage -for example, the nominal supply voltage in the UK is 230 V. But this is not necessarily the actual voltage at a particular time. A nomi…nal voltage is normally expressed together with the percentage by which it is permitted to vary from that stated value. For example, in the UK, the nominal voltage is expressed as: 230 V +10% / -6% --in other words it is allowed to vary between 216.2 and 253 V. The term, operating voltage, isn't actually defined anywhere, but is usually taken to mean the actual voltage supplied to a device at any particular instant, and this should always fall within the allowable range of the supply system's specified nominal voltage. The operating voltage can be found simply by measuring it with a voltmeter.
Line to line voltage is not the same as line to neutral voltage because line voltages are 120 degrees apart. They are related by: Line to neutral voltage * tan (120 degrees) =… Line to neutral voltage * 1.73. Additional Comment For delta-connected systems, the line voltage is the same as the phase voltage. For wye-connected systems, the line voltage is larger than the phase voltage by a factor of 1.732. The reason for this is as follows: Because any two phase voltages are displaced from each other by 120o, they must be added vectorially, not algebraically, to find the line voltage. As the above answer points out, this means that the relationship between the two is the square-root of 3, or 1.732.
The rated voltage of a motor listed on the nameplate is called the terminal voltage. This indicates the actual voltage on the motors terminals at which at which the manufactur…er designed to operate. Whereas, Nominal voltage is the design or configuration voltage of the electricity distribution system.
Phase, if you are referring to line, as power line from pole.
The term, 'nominal', simply means 'named'. For example, the nominal supply voltage for a residence in the UK is 230 V. But this doesn't mean that the actual supply voltage is …230 V, because the supply voltage is allowed to vary by -6% and +10% of the nominal voltage. In other words, the actual voltage could be anywhere within the range of 216.2 V to 253 V. In fact, during periods of heavy load, the actual voltage would tend towards the lower end of this range, whereas during periods of higher load, the actual voltage would vary towards the upper end.
Yes. By definition, a line-to-line voltage is indeed called a line voltage. For delta-connected, three-wire, systems comprise three line conductors. The line voltage is nume…rically equal to the phase voltage. For wye-connected, four-wire, systems comprise three line conductors and a neutral conductor. Any line-to-neutral voltage is called a phase voltage. The line voltage is 1.732 times the value of the phase voltage.
It depends on the system. For a delta-connected, three-wire, system, the line voltage is exactly the same as the phase voltage. For a wye-connected, four-wire, system, the li…ne voltage is 1.732 (the square-root of 3) times the phase voltage.
For questions of this type, it seems the main issue may be one of definitions and industry terms. See if this makes sense: Line voltage is a very ambiguous term. For instance…, say you are wiring a doorbell transformer. You feed 120V into the primary, and 18V comes out the secondary. The electrician would say the output is "low voltage" and the input is "line voltage". He simply means the building wiring, or "lines". Now, if you go out to the breaker panel, you will measure 120V from each "leg" to neutral, but you can also measure 240V from leg to leg. It's all line voltage. Line voltage simply means the voltage present in that particular power distribution system. Now the power in your house is "single phase" (well, in almost all homes, anyway). Single phase is fine for most anything, but motors are a special case. Motors need something to create a rotating magnetic field to get them turning. Single phase power doesn't have anything to do that, so they need some sort of a gimmick, like a capacitor, to create a "phase shift" to get the rotation. Single phase AC (alternating current) simply means the voltage goes positive then back down to zero, then negative then back up to zero. That's one complete cycle. The cycle is divided into 360 degrees, like a circle. The positive voltage goes from 0 to 180 degrees, and the negative half 180 back to 0. Now 3-phase power has, you guessed it, 3 hot wires. Each hot wire, when paired with a neutral, is a single-phase source. Heres the big difference: Phase A starts its positive cycle. When it is 120 degrees into the cycle, phase B starts going positive. When Phase B is 120 degrees finished with its cycle, phase C starts going positive. When phase C is 120 degrees into its cycle, that's a total of 360 degrees, and phase A is done with one cycle, and the whole process starts over. Picture 3 people doing "the wave" at a football game. Same principle. This time difference, or "phase shift" is what makes 3-phase power unique. 3-phase motors use the phase shift directly to produce the rotating magnetic field they need to turn. Think of 3 people in a circle, tossing a ball around. see the "circular" motion? Now picture two people tossing the ball back and forth. No circular motion there. That's the difference between single-phase and 3 phase. So, electricians use the term "phase" to refer to one of the three hot wires in a 3-phase (also correctly called multiphase or polyphase) power system. The term "phase" voltage is just as ambiguous as "line" voltage. To be accurate, you must specify whether you mean phase-to-phase voltage, or phase-to-neutral voltage. Confused? if you go into a large commercial building with 3-phase power, many times the incoming panel will have voltmeters on the front. In one building, the first meter will be labeled "phase-to-phase voltage", and the second meter will be labeled "phase-to-neutral voltage". Go into the building NEXT DOOR, and the same meters will be labeled "line-to-line voltage" and "line-to-neutral voltage". See? the terms are used pretty interchangably. In a 3-phase system, each phase, leg, or line has the same potential, or voltage (except for a very few wierd and pretty outdated systems). If you measure from phase A to Phase B you will get the same reading as B to C, also the same as C to A. So, measuring any two phases will tell you what the line voltage is, but that motor still needs all 3 phases to get the rotation. To understand the different voltages you find in a 3-phase system, see the related questions for another answer that relates to that subject.
Can i use a circuit breaker with 420V nominal voltage in 520V line voltage nominal current of circuit breaker is 1600A if I can how much current can pass from this circuit breaker?
NO! NO! NO! The circuit breaker must be rated for the line voltage used. Exceeding this limit can cause catastrophic failure! If you are really working on a 16…00A bus, stop right now, ang go hire a professional! Your question indicates you are not qualified to work on this gear. YOU ARE GOING TO KILL SOMEBODY. I'm not kidding about this. A breaker that is applied beyond its rating can arc over, and the resulting arc-flash can punch right through the panel cover, spraying vaporized metal on anyone unfortunate enough to be standing there. A 1600A bus can have a fault current of 20,000A OR MORE. This is not something to even think about working on unless you are trained and absolutely know what you are doing!
Your question is confusing and probably reflects certain misunderstandings. But I will attempt to give an answer. household single phase line voltage is 110 VAC, 11…5 VAC, or 120 VAC in the US and 230 VAC in most other countries household "two phase" line voltage is 220 VAC, 230 VAC, or 240 VAC in the US (this system was originally developed by Edison for his DC system, but after the US converted to AC it was retained and adapted, it is not generally used outside North America) industrial users usually use three phase, which depending on their industrial needs may be 240 VAC, 480 VAC, 600 VAC, etc. and could be either "delta" (3 wire) or "wye" (4 wire) configeration distribution system line voltage is usually a few thousand VAC to a few tens of thousand VAC transmission system line voltage is usually a few hundred thousand VAC to a few million VAC almost always "delta" (3 wire) configuration to reduce the cost of wire, sometimes on very long transmission lines voltage of about a million VDC are used