1.0Electrical Riddlehttps://electrical-riddle.com/enElectrical Riddlehttps://electrical-riddle.com/enrich600338<blockquote class="wp-embedded-content" data-secret="r3xSr5s26E"><a href="https://electrical-riddle.com/en/forums/reply/1594/">Reply To: Protection Riddle No.38 – Restricted earth fault protection and Inrush current</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://electrical-riddle.com/en/forums/reply/1594/embed/#?secret=r3xSr5s26E" width="600" height="338" title="“Reply To: Protection Riddle No.38 – Restricted earth fault protection and Inrush current” — Electrical Riddle" data-secret="r3xSr5s26E" 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> The inrush current flowing in the primary while energisation of the transformer is not of same magnitude in each phase, they are different in magnitude. Hence there will be phase currents of different magnitude and also it is not balanced through neutral. So there will be differential current in REF relay and hence it may … Read More »