bkit 220 volts?

[de PatAtas]

''yup..yun po ang madalas ku makita sa sa likod ng Ref,,Washing machine,,,atbp..yung green,,tapos yung white nsa PDX wire...ala pu ding kuryenti yu eh..

[jacks]

Green wire symbolizes neutral wire, not ground wire or return wiring. yung mga green na wiring o may green strip sa insulation dapat neutral wiring, ang uses nito ay kung may leak o induction sa equipment dito kaagad daraan ang kuryente para hindi makakuryente ng tao(safety purposes). At dapat maganda at pagkakabit sa earth grounding.

Hindi rin ito safe hawakan kung may leak ang equipment mo(lalo na kung hindi naka-earth ground). Daraan sa iyo yung kuryente.

[de PatAtas]

Green wire symbolizes neutral wire, not ground wire or return wiring. yung mga green na wiring o may green strip sa insulation dapat neutral wiring, ang uses nito ay kung may leak o induction sa equipment dito kaagad daraan ang kuryente para hindi makakuryente ng tao(safety purposes). At dapat maganda at pagkakabit sa earth grounding.

Hindi rin ito safe hawakan kung may leak ang equipment mo(lalo na kung hindi naka-earth ground). Daraan sa iyo yung kuryente.

' you mean,,parehas sila ng neutral wire nung dUn sa poste?,..

[jacks]

Nope. Yung green wire sa earth/chassis ground yan. It must be connected to earth ground to dump leakage or induction. With shortest path and less resistance.

Sa multi ground kasi ganito 1. supply line(hot line) 2. ground wire(return wire- to complete the circuit) 3. earth ground.

[ece.lourence]

nalilito po ako...

bakit po mas greater ang current sa thinner wire?

[,,V, (@_@) ,V,,]

^ Hi joanne 

[ece.lourence]

ala, may tinatanong ata ako eh.

[I n s i d e r 2010]

multi ground ac source po d2 sa amin

isang neutral (earth ground)
at isang hot line

ung nasa likod ng mga appliances na wire ay ibabaon or ikokonek sa earth ground

kaya nagsisilbing iisa yung ground at yung neutral d2 sa amin

[,,V, (@_@) ,V,,]

ala, may tinatanong ata ako eh.

Pasensya na.. Di ko napigilan ang aking sarili... Umiibig na yata ako

nalilito po ako...

bakit po mas greater ang current sa thinner wire?

Nu ba tan0ng m0? Ang alam ko thick wire ang gamit pag large currents

[piona]

"Tesla built Westinghouse a prototype motor, optimized for 60 Hz and 240 volts AC. Westinghouse's original system ran at 133 Hz, and not surprisingly, Tesla's motors failed to put out any power at that frequency. Westinghouse's own engineers tried to redesign the motor (Tesla would have nothing to do with redesign, insisting that Westinghouse change his generating network to 60 Hz and 240 volts). The rest is history, as Westinghouse gave in to Tesla (and more importantly, the laws of physics) and changed his grid to 60 Hz - our standard today. "


Meron po ba kayong alam o link papaano na arrive ni Tesla ang 240, 60Hz ?

[KANGARO]

[ece.lourence]

Pasensya na.. Di ko napigilan ang aking sarili... Umiibig na yata ako
Nu ba tan0ng m0? Ang alam ko thick wire ang gamit pag large currents

umiibig amp aahaha

eh bakit mas matipid sa transmission line ang 220v?

[rdpzycho]

example 100W load.

P = VI

110V

I = 100W/110V = 0.91A

220V

I = 100W/220V = 0.45A

to produce same power, kalahati lang ang current na kailangan ng 220V against 110V.

[alyas]

Walang kinalaman ang size ng conductor sa pagtitipid sa transmission line.  It all has to do with power losses transmitting electricity through the conductor.  For the same size conductor, at 220V, there is less current flowing through the line compared to 110V and hence lower voltage drop accross the whole power line which results to less power wasted sa line.

 

[,,V, (@_@) ,V,,]

umiibig amp aahaha

Bakit? Masama na ba umibig ngaun?

[piona]

parang ganito ata yan sa Ohm's Law:

R = resistance (to the flow of electrical current)
V = voltage (emf)
I  = current (flow of free elecrons)

P = I^2 R

so power loss is squared with the current.

R can be compensated by making transmission line thicker or bigger to minimize the resistance of the flow of electrical currents pero mahal naman.

[,,V, (@_@) ,V,,]

Walang kinalaman ang size ng conductor sa pagtitipid sa transmission line.  It all has to do with power losses transmitting electricity through the conductor.  For the same size conductor, at 220V, there is less current flowing through the line compared to 110V and hence lower voltage drop accross the whole power line which results to less power wasted sa line.

 

Ayun naalala ko na ung cnabi ng pr0f ko kung bakit 220v sa pinas.. Dahil sa transmission line losses..

[piona]

may tanong din ako bakit 220Vac, bat hindi 222V o di kaya 221 o 225V... bakit 220? saan ba nanggalimg ang numerong ito  
 

[piona]

From Wiki  

http://en.wikipedia.org/wiki/Mains_electricity


History of voltage and frequency
 
Voltage & frequency around the world
 
The system of three-phase alternating current electrical generation, transmission, and distribution was developed in the 19th century by Nikola Tesla, George Westinghouse and others. Thomas Edison developed direct current (DC) systems at 110 V and this was claimed to be safer in the battles between proponents of AC and DC supply systems (the War of Currents). Edison chose 110 volts to make high-resistance carbon filament lamps both practical and economically competitive with gas lighting. While higher voltages would reduce the current required for a given quantity of lamps, the filaments would become increasingly fragile and short-lived. Edison selected 100 volts for the lamp as a compromise between distribution costs and lamp costs. Generation was maintained at 110 volts to allow for a voltage drop between generator and lamp.

In the 1880s only carbon-filament incandescent lamps were available, designed for a voltage of around 100 volts. Later metal filament lamps became feasible. In 1899, the Berliner Elektrizitäts-Werke (BEW), a Berlin electrical utility, decided to greatly increase its distribution capacity by switching to 220 volt nominal distribution, taking advantage of the higher voltage capability of metal filament lamps. The company was able to offset the cost of converting the customer's equipment by the resulting saving in distribution conductors cost. This became the model for electrical distribution in Germany and the rest of Europe and the 220-volt system became common. North American practice remained with voltages near 110 volts for lamps. [7]

In 1883 Edison patented a three wire distribution system to allow DC generation plants to serve a wider radius of customers. This saved on copper costs since lamps were connected in series on a 220 volt system, with a neutral conductor connected between to carry any unbalance between the two sub-circuits. This was later adapted to AC circuits. Most lighting and small appliances ran on 120 V, while big appliances could be connected to 240 V. This system saved copper and was backward-compatible with existing appliances. Also, the original plugs could be used with the revised system.

Main article: Utility frequency
At the end of the 19th century, Westinghouse in the US decided on 60 Hz and AEG in Germany decided on 50 Hz, eventually leading to the world being mostly divided into two frequency camps. Most 60 Hz systems are nominally 120 volts and most 50 Hz nominally 230 volts.

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i think tesla formulated the 60 hz frequency (considering the metal stress maybe) for his first electric motor design but a german first electrik company decided the 220V     ano sa palagay nyo mga sis??

[rdpzycho]

Walang kinalaman ang size ng conductor sa pagtitipid sa transmission line.  It all has to do with power losses transmitting electricity through the conductor.  For the same size conductor, at 220V, there is less current flowing through the line compared to 110V and hence lower voltage drop accross the whole power line which results to less power wasted sa line.

AFAIR, large part of it is losses due to voltage drop to finite resistance in the transmission, and one part is cost of transmission line (use of larger diameter to compensate for voltage drop). dahil para ma-achieve 'yung same required maximum voltage drop, kailangang gumamit ng ~3 times conductor area sa half voltage (110V), resulting in ~3 times more volume of copper needed than 220V.

Over long distances, larger conductors become expensive, and it is preferable to redesign the circuit to operate at a higher voltage. Doubling the voltage halves the current required to deliver the same amount of power, halving the voltage drop, and an additional doubling in efficiency is realized because that drop is a smaller fraction of the total voltage.
This is the motivation for commercial high voltage electrical power distribution, and for the use of the +12V power supply rail for high-power loads in modern personal computers.

IIRC, sa US 220V ang entry then split to 110V with one wire to GND, para mas efficient ang distribution at mas maliliit din ang wires na gagamitin sa bahay with power appliances.