Thank Slavag for ur consideration, but now I understand,it's fault of 7UT6 relay technical manual. In manual of version 4.0, they wrote like above " Note that the restricted earth fault protection (cannot be applied for busbars or auto-transformers". Then in version 4.6, they correted it, just...
Hi everyone, I'm reading the technical manual of numerical relay (SIPROTECT 7UT6), and they say that" Note that the restricted earth fault protection (cannot be applied for busbars or auto-transformers". Someone could tell me the reason?