https://wiki.restarters.net/index.php?title=AC_and_DC&feed=atom&action=historyAC and DC - Revision history2024-03-29T15:30:20ZRevision history for this page on the wikiMediaWiki 1.38.2https://wiki.restarters.net/index.php?title=AC_and_DC&diff=2225&oldid=prevPleriche at 22:46, 3 February 20192019-02-03T22:46:42Z<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 22:46, 3 February 2019</td>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">This page explains </del>the difference between <del style="font-weight: bold; text-decoration: none;">AC </del>and <del style="font-weight: bold; text-decoration: none;">DC</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">You may have heard of AC and DC but maybe never quite understood </ins>the difference between <ins style="font-weight: bold; text-decoration: none;">them, or why we sometimes use one </ins>and <ins style="font-weight: bold; text-decoration: none;">sometimes the other. All is revealed in this page.</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC is what nearly all electronic equipment needs internally to operate; whether you're trying to play a CD or browse the Internet on your computer, the electronics needs a constant and unvarying source of power in order to do its job. Imagine trying to drive a car if the engine kept cutting out every few yards!</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC is what nearly all electronic equipment needs internally to operate; whether you're trying to play a CD or browse the Internet on your computer, the electronics needs a constant and unvarying source of power in order to do its job. Imagine trying to drive a car if the engine kept cutting out every few yards!</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, two reversals making a complete cycle and bringing you back to where you started. That's to say it completes 50 <del style="font-weight: bold; text-decoration: none;">forward</del>/backwards cycles every second, or has a ''frequency'' of 50Hz (Hertz). This is called Alternating Current, or AC, since the direction continually alternates between one direction and the other. The figure shows a graph of the voltage against time for 3 cycles, from which you can see that it's constantly varying.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, two reversals making a complete cycle and bringing you back to where you started. That's to say it completes 50 <ins style="font-weight: bold; text-decoration: none;">forwards</ins>/backwards cycles every second, or has a ''frequency'' of 50Hz (Hertz). This is called Alternating Current, or AC, since the direction continually alternates between one direction and the other. The figure shows a graph of the voltage against time for 3 cycles, from which you can see that it's constantly varying <ins style="font-weight: bold; text-decoration: none;">like the motion of a pendulum</ins>.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution when many applications then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. However, AC has several important advantages.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution when many applications then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. However, AC has several important advantages.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can very easily be converted from a high to a low voltage or vice versa using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over <del style="font-weight: bold; text-decoration: none;">large </del>distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can very easily be converted from a high to a low voltage or vice versa using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over <ins style="font-weight: bold; text-decoration: none;">long </ins>distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Another big advantage is a little more subtle. Suppose you need to transmit 1MW (a megawatt) from A to B. You will need 2 wires of a certain thickness to complete the circuit. If you now need to transmit 3MW, <del style="font-weight: bold; text-decoration: none;">you will need 6 </del>wires of the same thickness. But no, you can manage with only 3!</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Another big advantage is a little more subtle. Suppose you need to transmit 1MW (a megawatt) from A to B. You will need 2 wires of a certain thickness to complete the circuit. If you now need to transmit 3MW, <ins style="font-weight: bold; text-decoration: none;">with </ins>wires of the same thickness<ins style="font-weight: bold; text-decoration: none;">, you would need 6 of them</ins>. But no, you can manage with only 3!</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Suppose you start off with 6 wires and feed each of the 3 pairs with 1MW of AC, but with the AC supplies equally spaced out of phase like 3 spokes of a wheel. Suppose you also decide to replace the 3 return wires by one wire of 3 times the thickness. If you now measure the current in that return wire, you might be surprised to find there isn't any! This is because at any instant one of the 3 pairs will be supplying current in one direction and the other <del style="font-weight: bold; text-decoration: none;">2 </del>will be supplying it in the reverse direction. Between them, <del style="font-weight: bold; text-decoration: none;">they </del>can exactly soak up the return current of the first. So you can dispense with the return wires and still send 3MW with only 3 wires, saving 50% of the cost of wire needed<del style="font-weight: bold; text-decoration: none;">. </del>This is what is meant by a 3 phase supply.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Suppose you start off with 6 wires and feed each of the 3 pairs with 1MW of AC, but with the AC supplies equally spaced out of phase like 3 spokes of a wheel. Suppose you also decide to replace the 3 return wires by one wire of 3 times the thickness. If you now measure the current in that return wire, you might be surprised to find there isn't any! This is because at any instant one of the 3 pairs will be supplying current in one direction and the other <ins style="font-weight: bold; text-decoration: none;">two </ins>will be supplying it in the reverse direction. Between them, <ins style="font-weight: bold; text-decoration: none;">those two </ins>can exactly soak up the return current of the first. So you can dispense with the return wires and still send 3MW with only 3 wires, saving 50% of the cost of wire needed<ins style="font-weight: bold; text-decoration: none;">! </ins>This is what is meant by a 3 phase supply.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it. <del style="font-weight: bold; text-decoration: none;">Furthermore</del>, 3 phase is just as easy to generate. All you need is 3 coils equally spaced around the spinning magnet.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it. <ins style="font-weight: bold; text-decoration: none;">What's more</ins>, 3 phase is just as easy to generate. All you need is 3 coils equally spaced around the spinning magnet.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=1733&oldid=prevPleriche: /* So Why? */2017-10-15T20:17:07Z<p><span dir="auto"><span class="autocomment">So Why?</span></span></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">DC is more efficient also for very long transmission lines. With AC you're continually pushing the electricity during one half cycle then sucking it back in order to push it the other way in the next. If your wire is hundreds of miles long then some of the electricity will never have got to do anything useful at the far end before it starts getting sucked back again!</ins></div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=1521&oldid=prevPleriche: /* So Why? */2017-07-21T09:44:58Z<p><span dir="auto"><span class="autocomment">So Why?</span></span></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Suppose you start off with 6 wires and feed each of the 3 pairs with 1MW of AC, but with the AC supplies equally spaced out of phase like 3 spokes of a wheel. Suppose you also decide to replace the 3 return wires by one wire of 3 times the thickness. If you now measure the current in that return wire, you might be surprised to find there isn't any! This is because at any instant one of the 3 pairs will be supplying current in one direction and the other 2 will be supplying it in the reverse direction. Between them, they can exactly soak up the return current of the first. So you can dispense with the return wires and still send 3MW with only 3 wires, saving 50% of the cost of wire needed. This is what is meant by a 3 phase supply.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Suppose you start off with 6 wires and feed each of the 3 pairs with 1MW of AC, but with the AC supplies equally spaced out of phase like 3 spokes of a wheel. Suppose you also decide to replace the 3 return wires by one wire of 3 times the thickness. If you now measure the current in that return wire, you might be surprised to find there isn't any! This is because at any instant one of the 3 pairs will be supplying current in one direction and the other 2 will be supplying it in the reverse direction. Between them, they can exactly soak up the return current of the first. So you can dispense with the return wires and still send 3MW with only 3 wires, saving 50% of the cost of wire needed. This is what is meant by a 3 phase supply.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it<ins style="font-weight: bold; text-decoration: none;">. Furthermore, 3 phase is just as easy to generate. All you need is 3 coils equally spaced around the spinning magnet</ins>.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=1520&oldid=prevPleriche: /* So Why? */2017-07-21T09:41:06Z<p><span dir="auto"><span class="autocomment">So Why?</span></span></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 09:41, 21 July 2017</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution when many applications then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. <del style="font-weight: bold; text-decoration: none;">In fact</del>, AC has several important advantages.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution when many applications then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. <ins style="font-weight: bold; text-decoration: none;">However</ins>, AC has several important advantages.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can very easily be converted from a high to a low voltage or vice versa using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over large distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can very easily be converted from a high to a low voltage or vice versa using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over large distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial<del style="font-weight: bold; text-decoration: none;">, </del>so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Another big advantage is a little more subtle. Suppose you need to transmit 1MW (a megawatt) from A to B. You will need 2 wires of a certain thickness to complete the circuit. If you now need to transmit 3MW, you will need 6 wires of the same thickness. But no, you can manage with only 3!</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Suppose you start off with 6 wires and feed each of the 3 pairs with 1MW of AC, but with the AC supplies equally spaced out of phase like 3 spokes of a wheel. Suppose you also decide to replace the 3 return wires by one wire of 3 times the thickness. If you now measure the current in that return wire, you might be surprised to find there isn't any! This is because at any instant one of the 3 pairs will be supplying current in one direction and the other 2 will be supplying it in the reverse direction. Between them, they can exactly soak up the return current of the first. So you can dispense with the return wires and still send 3MW with only 3 wires, saving 50% of the cost of wire needed. This is what is meant by a 3 phase supply.</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Theory]]</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=1302&oldid=prevPleriche at 22:50, 25 December 20162016-12-25T22:50:20Z<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 22:50, 25 December 2016</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l28">Line 28:</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the frequency of national grid.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>[[Category:<del style="font-weight: bold; text-decoration: none;">General</del>]]</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[[Category:<ins style="font-weight: bold; text-decoration: none;">Theory</ins>]]</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=769&oldid=prevPleriche: /* So Why? */2015-07-25T21:10:37Z<p><span dir="auto"><span class="autocomment">So Why?</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 21:10, 25 July 2015</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution<del style="font-weight: bold; text-decoration: none;">, </del>when many <del style="font-weight: bold; text-decoration: none;">application </del>then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. <del style="font-weight: bold; text-decoration: none;">However</del>, AC has several important advantages.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Why would AC be used for power distribution when many <ins style="font-weight: bold; text-decoration: none;">applications </ins>then require the additional complication and expense of converting it to DC before it can be used? In fact, the earliest power distribution systems used DC. <ins style="font-weight: bold; text-decoration: none;">In fact</ins>, AC has several important advantages.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can <del style="font-weight: bold; text-decoration: none;">be </del>very easily converted from a high to a low voltage<del style="font-weight: bold; text-decoration: none;">, </del>or vice versa<del style="font-weight: bold; text-decoration: none;">, </del>using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over large distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The main advantage of AC is that it can very easily <ins style="font-weight: bold; text-decoration: none;">be </ins>converted from a high to a low voltage or vice versa using a [[Basic_electronic_components#Transformers|transformer]]. Transformers don't work on DC. A high voltage (or electrical pressure) is very good for pushing electricity over large distances, over which the resistance to the flow would mount up. This would be extremely dangerous if fed directly into the home, and a transformer in a neighbourhood substation converts it to a more manageable 240V for feeding into the home.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial, so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For many purposes such as heating, and historically for old fashioned filament lamps, the direction of flow is immaterial, so AC is just as good as DC. All but the simplest electric motors work just as well with AC as DC and some only work on AC. So when universal [[Electric_motors#DC_and_Universal_.28AC.2FDC.29_Motors|AC/DC motors]] were invented, the case for AC power transmission became compelling. In fact, AC is easier to generate as all you need is a rotating magnet and a coil of wire. Positive and negative voltages are generated alternately in the coil as the magnetic field from the North and South poles of the magnet pass through it.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the national grid.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the <ins style="font-weight: bold; text-decoration: none;">frequency of </ins>national grid.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:General]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:General]]</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=768&oldid=prevPleriche: /* Practical Application */2015-07-25T21:05:39Z<p><span dir="auto"><span class="autocomment">Practical Application</span></span></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 21:05, 25 July 2015</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Probably the only time you need to understand AC and DC is if you are replacing a power supply, such as a wall cube type of power supply for a radio or rechargeable power tool. The output voltage should be marked on it such as "12V DC". Whether the output is marked as AC or (more usually) DC, any replacement must be the same.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Probably the only time you need to understand AC and DC is if you are replacing a power supply, such as a wall cube type of power supply for a radio or rechargeable power tool. The output voltage should be marked on it such as "12V DC". Whether the output is marked as AC or (more usually) DC, any replacement must be the same.</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">The mains frequency is 50Hz in many parts of the world, but 60Hz is the standard in North and much of South America and a few other countries. The much higher frequency of 400Hz is used in aircraft as this allows transformers and motors to be made a lot smaller and lighter. However, long distance transmission of power at higher frequencies becomes considerably less efficient.</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=767&oldid=prevPleriche: /* The Basics */2015-07-25T20:45:33Z<p><span dir="auto"><span class="autocomment">The Basics</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 20:45, 25 July 2015</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[file:AC-graph.png|275px|thumb|right|AC waveform]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[file:AC-graph.png|275px|thumb|right|AC waveform]]</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>DC is what nearly all electronic equipment needs to operate; whether you're trying to play a CD or browse the Internet on your computer, the electronics needs a constant and unvarying source of power in order to do its job. Imagine trying to drive a car if the engine kept cutting out every few yards!</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>DC is what nearly all electronic equipment needs <ins style="font-weight: bold; text-decoration: none;">internally </ins>to operate; whether you're trying to play a CD or browse the Internet on your computer, the electronics needs a constant and unvarying source of power in order to do its job. Imagine trying to drive a car if the engine kept cutting out every few yards!</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, <del style="font-weight: bold; text-decoration: none;">that</del>'s to say it completes 50 forward/backwards cycles every second, <del style="font-weight: bold; text-decoration: none;">and so </del>is called Alternating Current, or AC, since the direction alternates. The figure shows a graph of the voltage against time, from which you can see that it's constantly varying.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, <ins style="font-weight: bold; text-decoration: none;">two reversals making a complete cycle and bringing you back to where you started. That</ins>'s to say it completes 50 forward/backwards cycles every second, <ins style="font-weight: bold; text-decoration: none;">or has a ''frequency'' of 50Hz (Hertz). This </ins>is called Alternating Current, or AC, since the direction <ins style="font-weight: bold; text-decoration: none;">continually </ins>alternates <ins style="font-weight: bold; text-decoration: none;">between one direction and the other</ins>. The figure shows a graph of the voltage against time <ins style="font-weight: bold; text-decoration: none;">for 3 cycles</ins>, from which you can see that it's constantly varying.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Practical Application==</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=694&oldid=prevPleriche at 22:09, 30 May 20152015-05-30T22:09:33Z<p></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 22:09, 30 May 2015</td>
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<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">This page explains the difference between AC and DC</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Appliances often have markings such as "240V AC" or "12V DC". This page explains the difference between AC and DC and why it matters.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Appliances often have markings such as "240V AC" or "12V DC". This page explains the difference between AC and DC and why it matters.</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, that's to say it completes 50 forward/backwards cycles every second, and so is called Alternating Current, or AC, since the direction alternates. The figure shows a graph of the voltage against time, from which you can see that it's constantly varying.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>By contrast, mains electricity reverses direction 100 times per second, that's to say it completes 50 forward/backwards cycles every second, and so is called Alternating Current, or AC, since the direction alternates. The figure shows a graph of the voltage against time, from which you can see that it's constantly varying.</div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==Practical Application==</ins></div></td></tr>
<tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Probably the only time you need to understand AC and DC is if you are replacing a power supply, such as a wall cube type of power supply for a radio or rechargeable power tool. The output voltage should be marked on it such as "12V DC". Whether the output is marked as AC or (more usually) DC, any replacement must be the same.</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==So Why?==</div></td></tr>
</table>Plerichehttps://wiki.restarters.net/index.php?title=AC_and_DC&diff=693&oldid=prevPleriche at 22:01, 30 May 20152015-05-30T22:01:55Z<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 22:01, 30 May 2015</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1">Line 1:</td>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">This page is work in progress. Come back soon!</del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Summary==</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Appliances often have markings such as "240V AC" or "12V DC". This page explains the difference between AC and DC and why it matters.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Appliances often have markings such as "240V AC" or "12V DC". This page explains the difference between AC and DC and why it matters.</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the national grid.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DC power is still used in a few specialized cases. For example, cross-border power sharing often uses DC as it would be impracticable to synchronise the cycles of AC between two independent power grids in different countries. For a similar reason, it is used in wind farms for aggregating the power from individual wind turbines since it would be almost impossible to synchronise all the individual turbines to the national grid.</div></td></tr>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">==External links==</del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">* External links (if any) as bullet points.</del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">* If non, delete this section.</del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:General]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:General]]</div></td></tr>
</table>Pleriche