Home » English riddles » Protection » Protection Question No.16 – Restricted Earth Fault » Reply To: Protection Question No.16 – Restricted Earth Fault Reply To: Protection Question No.16 – Restricted Earth Fault 2021-08-03 at 11:08 am #2398 Sinnadurai Sripadmanaban What is the purpose of stanby earthfault relay?. Do we need both REF and SEF in all cases?>