This post describes the CT requirements for Relion 670 Relays applications.
To see other supported relays, click here.
Rated equivalent secondary e.m.f. requirements
Busbar protection
Distance protection
Breaker failure protection
Transformer differential protection
Restricted earth fault protection (low impedance differential) protection
Non-directional instantaneous and definitive time, phase and residual overcurrent protection
Non-directional inverse time delayed phase and residual overcurrent protection
Generator differential protection
Example 1 – (3 parts)
Example 2 – (3 parts)
Line differential protection
Directional phase & residual overcurrent protection
Current transformer requirements for CTs according to other standards
Current transformers according to IEC 61869-2, class P, PR
Current transformers according to IEC 61869-2, class PX, PXR (and old IEC 60044-6, class TPS and old British Standard, class X)
Current transformers according to ANSI/IEEE
