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Short distance transmission of power is done at higher voltage or higher current?
Wiki User
∙ 14y ago
High voltage is used to transfer power over long distances ONLY because the gauge of the wire can be smaller. Power transfer is always most efficient at the operating voltage if the size of wire is not an issue.
Wiki User
∙ 14y ago
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Why you use ac for transmission?
AC is used for transmission because AC can be stepped up in voltage with a transformer, and then stepped back down at the destination. Since power is voltage times current, a higher voltage requires a smaller current to achieve the same power. Since the current carrying capacity of wires is based on wire size, a smaller wire size can be used to transmit the lower current.
Why are transformers used to increase the voltage before transmission?
Using a higher voltage reduces power losses during transmission.
What happen when voltage decreases and current increases?
Yes. As long as the load stays the same. Voltage equals the resistance of the load times the current or amperage. Or , in this case, as an example, if the load is the same, the voltage is 240 and current is 10 amps. At 120 volts, the current is 20 amps. Current x resistance(or the load)=voltage. With simple math, the equation can be moved around.
Why do the transmission cables need to be thicker when power is transmitted at a lower voltage over long distances?
High-voltage transmission relies on the fact that for a given amount of power (watts), as the voltage goes up, the current (amps) goes down. The main issue with long distance transmission is voltage drop, which is proportional to current. Consider a transmission system supplying a 1 megawatt load. At 132,000 volts (3-phase), the current will be about 4.4 Amps (132kV X 4.379A X 1.73 = 1MW). Now, even 14 gauge wire would carry 4 or 5 amps, But the wire will have to be much larger than that to limit voltage drop to an acceptable level. The cost of the line itself is relatively small, BUT you have to buy transformers, one for each end! Utility-grade high voltage transformers are enormously expensive, and the hardware for high voltage transmission is also more expensive. Now consider a hypothetical transmission system supplying the same 1MW load, but now our transmission voltage is 4,160 volts. The current would now be 139 Amps! (4,160V X 138.9A X 1.73 = 1MW). You can see that the conductors must be very large to carry that much current. The problem is we still have to make the conductors larger to make up for voltage drop, and we end up with huge conductors. Of course, now you don't have to buy expensive high-voltage transformers! This is an extreme example just to make the point, by the way. At some distance, the cost of the transformers and associated hardware will equal the cost to eliminate them and just use larger conductors. At any distance less than that, it will be cheaper to use the low-voltage, high current setup. At any greater distance, the cost of the transformers, etc. will be more than offset by the cheaper transmission infrastructure (smaller conductors, etc.).
What is relation between voltage and conductors?
Your question is unclear. But, if you are asking what the relationship between voltage and the distance between conductors is, then the higher the voltage, the greater the distance must be.
What is the reason why it is better to use high voltage instead of low voltage on long distance?
High voltage reduces the amount of energy lost due to the resistance of the transmission material (conductor), by reducing the current. In other words, increasing voltage reduces current, and lower current means less resistance loss. Voltage and current have an inverse relationship, and later on when the electricity gets closer to the consumer, voltages can be decreased which increases the current. Increased current means higher resistance, and it is resistance that does the work.
When a circuit is inductive the current has what voltage?
This doesn't make sense, "current" is "amperage" so the higher the voltage the lower the amperage, and the lower the voltage the higher the amperage.
Why you use ac for transmission?
AC is used for transmission because AC can be stepped up in voltage with a transformer, and then stepped back down at the destination. Since power is voltage times current, a higher voltage requires a smaller current to achieve the same power. Since the current carrying capacity of wires is based on wire size, a smaller wire size can be used to transmit the lower current.
Why are transformers used to increase the voltage before transmission?
Using a higher voltage reduces power losses during transmission.
Why is voltage increased in transmission?
Voltage is increased while transmission of power because it yield less losses due to the current carried by the line conductors.Losses = I*I*R, where I is current and R is resistance of lineHigher the voltage lower the current because the power remains the same.But, after certain limits you cannot increase the voltage further due to technical limitations like designing of transformers and the clearance between phase of transmission line and line to ground etc.AnswerFor any given load, the higher the supply voltage, the lower the resulting load current. This enables conductors with relatively small diameters to be used. Using low voltages would prohibit the use of reasonable-sized conductors. This it the primary reason for using high transmission voltages. Line losses, as described above, are a secondary reason.
What happen when voltage decreases and current increases?
Yes. As long as the load stays the same. Voltage equals the resistance of the load times the current or amperage. Or , in this case, as an example, if the load is the same, the voltage is 240 and current is 10 amps. At 120 volts, the current is 20 amps. Current x resistance(or the load)=voltage. With simple math, the equation can be moved around.
Electrons flow from areas of higher to lower voltage or from areas of lower to higher voltage?
Electronsflow from areas of lower to higher voltage, while Current flow from areas higher to lower voltage.
Why is it important to select a high voltage and low current during trnsmission of electricity?
For a given load, the higher the supply voltage, the lower the load current. By using higher transmission voltages, the resulting lower currents ensure (a) minimal voltage drops along the lines, (b) conductors of practical size, and (c) less line losses.
High voltage will trip a circuit breaker?
A higher voltage means that a higher current will flow in the same load. It is the current that causes the breaker to trip.
Your usage 415v why getting 33kv?
If you want 415 volts, and you are getting 33,000 volts something is horribly wrong. Voltage is stepped up / stepped down for transmission to "load centers" (you) because of the "I^2 R" losses. Power = current squared times the resistance. The resistance of the conductor that is carrying your power is finite and cannot be made to be zero (unless you're using superconductors), so to minimize power loss incurred by transmission to you, the current must be decreased. This is accomplished by stepping the voltage up to a higher value (since power = voltage / current, the same power at a higher voltage can be delivered with a smaller current, thus less transmission loss). Voltage and current are stepped up/down using transformers. I hope this covers your question.
What is electrical pressure?
Electro motive force = EMF = Voltage.
What is the function of step up transformer?
The step-up transformer steps up the input voltage to a higher level so that it can be transmitted over a transmission line using smaller conductors. By the power law, power equals volts times amps, so you can achieve the same power with higher voltage and lower current, but the wire size is based only on current.On the other end, step-down transformers reduce the high voltage back to usable levels.
