Downloading Lecture 21a - Basic Concept of Differential Protection.pdf (741.09 KB) If the download doesn't start, Clik here Recomended Files Lecture 4a - Basic Concept of Transformer.pdf Lecture 21a - Basic Concept of Differential Protection.pdf acct615_lecture01.m4a Lecture with GM Yasser Seirawan (Basic Development - Avoiding a Trapped Bishop) - 2013.07.18.mp4