D Current Transformer Requirements - Siemens SIPROTEC 4 Manual

D Current Transformer Requirements
The requirements for phase current transformers are usually determined by the overcurrent time protection,
particularly by the high-current element settings. Besides, there is a minimum requirement based on experi-
ence.
The recommendations are given according to the standard IEC 60044-1.
The standards IEC 60044-6, BS 3938 and ANSI/IEEE C 57.13 are referred to for converting the requirement into
the knee-point voltage and other transformer classes.
D.1 Accuracy limiting factors
D.2 Class conversion
D.3 Cable core balance current transformer
SIPROTEC 4, 7SJ80, Manual
E50417-G1140-C343-A8, Edition 12.2017
456
457
458
455