Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Static relay
open-in-new
<h2 id="structure">Structure</h2> <p>A static relay consists of:<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p> <ul><li>An input circuit that measures the value of desired property</li> <li>A <a href="/facts/Comparator/jfk32rf6">comparator</a> circuit that compares the measured value to a preset threshold</li> <li>An optional time delay circuit that controls the timing of the switch action after the input has reached the threshold</li> <li>A power supply for the static relay circuits</li></ul> <p>For example, an overcurrent protective relay may have an <a href="/facts/AC_to_DC_power_supply/4A8zBRHn">AC to DC power supply</a> for the input circuit, a level detector circuit and an RC time delay circuit.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> While early comparators used discrete <a href="/facts/Transistor/Bmr8zwL0">transistor</a> circuits, modern designs use <a href="/facts/Operational_amplifier/hunKdYb9">operational amplifiers</a>. </p> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>BHEL, Bharat Heavy Electricals Limited (2005). "Chapter 9". Handbook of Switchgears. New Delhi: Tata McGraw-Hill. ISBN 9780070532380. <a href="9780070532380" target="_blank">9780070532380</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>BHEL, Bharat Heavy Electricals Limited (2005). "Chapter 9". Handbook of Switchgears. New Delhi: Tata McGraw-Hill. ISBN 9780070532380. <a href="9780070532380" target="_blank">9780070532380</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>BHEL, Bharat Heavy Electricals Limited (2005). "Chapter 9". Handbook of Switchgears. New Delhi: Tata McGraw-Hill. ISBN 9780070532380. <a href="9780070532380" target="_blank">9780070532380</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Alstom (2011). "Chapter 7". Network Protection And Automation Guide. <a href="http://electrical-engineering-portal.com/download-center/books-and-guides/electrical-engineering/automation-guide" target="_blank">http://electrical-engineering-portal.com/download-center/books-and-guides/electrical-engineering/automation-guide</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>BHEL, Bharat Heavy Electricals Limited (2005). "Chapter 9". Handbook of Switchgears. New Delhi: Tata McGraw-Hill. ISBN 9780070532380. <a href="9780070532380" target="_blank">9780070532380</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>BHEL, Bharat Heavy Electricals Limited (2005). "Chapter 9". Handbook of Switchgears. New Delhi: Tata McGraw-Hill. ISBN 9780070532380. <a href="9780070532380" target="_blank">9780070532380</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> </ol>