1.0Electrical Riddlehttps://electrical-riddle.com/faElectrical Riddlehttps://electrical-riddle.com/farich600338<blockquote class="wp-embedded-content" data-secret="8aSDdApyka"><a href="https://electrical-riddle.com/fa/forums/topic/148/">Protection Riddle No.12 – Inability of Earth fault protection system</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://electrical-riddle.com/fa/forums/topic/148/embed/#?secret=8aSDdApyka" width="600" height="338" title="“Protection Riddle No.12 – Inability of Earth fault protection system” — Electrical Riddle" data-secret="8aSDdApyka" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://electrical-riddle.com/wp-includes/js/wp-embed.min.js </script>As you know, for earth fault protection of electrical system, the residual current measurement is often performed using the three line CTs. As you know, for earth fault protection of electrical system, the residual current measurement is often performed using the three line CTs. But in this case the protective relay must be slightly time-delayed … ادامه »https://electrical-riddle.com/wp-content/uploads/2021/08/115963135_42.gif