Earth leakage circuit breaker (ELCB) sensor, part 610024-03, for Hanovia medium-pressure ultraviolet disinfection systems. Medium-pressure lamp gear runs at high voltage in a wet plant room, so the earth leakage sensor is the protective device that detects current escaping to earth — through a damaged lamp lead or a flooded chamber — and trips the supply before it becomes a shock or fire risk. It is a safety-critical item and should be replaced with the specified part rather than a generic equivalent. Reference number 2286-0911.