History
ELCBs were mainly used on TT earthing systems. Nowadays, ELCBs have been mostly replaced by residual-current devices (RCDs). However many ELCBs are still in use.
Early ELCBs responded to sine wave fault currents, but not to rectified fault current. Over time, filtering against nuisance trips has also improved. Early ELCBs thus offer a little less safety and higher risk of nuisance trip. The ability to distinguish between a fault condition and non-risk conditions is called discrimination.
ELCB manufacturers include: Legrand, Havells, ABB, Siemens AG, Areva T&D, Camsco, Telemecanique, Orion Italia, Crabtree, MEM.
Read more about this topic: Earth Leakage Circuit Breaker
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