Core Balanced Current Transformers & ELR

Stefan Core Balanced Current Transformers & Earth Leakage Relays

Stefan Electric's earth leakage protection pairs a core balanced current transformer (CBCT) with a configurable earth leakage relay (ELR). The CBCT senses the vector-sum current through all conductors passing through its aperture; any imbalance caused by a leakage path is picked up by the relay, which trips at a set threshold after a configurable delay.

CBCTs are available in a range of aperture sizes from 35mm up to 310mm round, plus rectangular formats, so the same protection scheme scales from single feeders to large busbar runs and cable bundles.