1) Current Transformer IS 16227 PART 1:2016, IEC 61869-1:2007

IS 16227 PART 2:2016,IEC 61869-2:2012
2) Potential Transformer IS 16227 PART 1:2016, IEC 61869-1:2007

IS 16227 PART 3:2015, IEC 61869-3:2011