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<oembed><version>1.0</version><provider_name>Electrical Riddle</provider_name><provider_url>https://electrical-riddle.com/en</provider_url><author_name>Electrical Riddle</author_name><author_url>https://electrical-riddle.com/en</author_url><title>- Electrical Riddle</title><type>rich</type><width>600</width><height>338</height><html>&lt;blockquote class="wp-embedded-content" data-secret="DUxGNi8Puf"&gt;&lt;a href="https://electrical-riddle.com/en/forums/reply/1169/"&gt;Reply To: Electrical riddle no.5 &ndash; DC Control systems and polarity&lt;/a&gt;&lt;/blockquote&gt;&lt;iframe sandbox="allow-scripts" security="restricted" src="https://electrical-riddle.com/en/forums/reply/1169/embed/#?secret=DUxGNi8Puf" width="600" height="338" title="&#x201C;Reply To: Electrical riddle no.5 &ndash; DC Control systems and polarity&#x201D; &#x2014; Electrical Riddle" data-secret="DUxGNi8Puf" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"&gt;&lt;/iframe&gt;&lt;script&gt;
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</html><description>Generally electrical equipment that used in auxiliary control systems shown in bottom of pages. Therefore equipment (relay etc.) that usually installed in field area is directly connected to one of two polarity continuously, and other polarity connected to the other terminal of equipment via auxiliary contact of controller devices that shown on top of pages &hellip;  Read More &raquo;</description></oembed>
