Where: In distribution panels of commercial buildings, typically downstream of the main incomer, protecting circuits feeding floors, offices, HVAC systems, and lighting.

Why: To detect leakage currents caused by insulation faults or faulty equipment and trip the circuit before it poses a shock hazard or causes fire, ensuring personnel safety, equipment protection, and compliance with electrical safety standards.

Where: In UPS-backed power panels and IT server room distribution boards supplying critical loads such as server racks, network switches, and storage systems.

Why: To detect and isolate earth leakage currents from faulty UPS circuitry, power distribution units, or server power supplies before they lead to electric shock, fire hazards, or downtime — ensuring equipment protection, personnel safety, and uninterrupted operation of mission-critical IT infrastructure.

Where: Installed in manufacturing plants, process industries, or heavy-load facilities where motors can be powered from two separate incoming sources (e.g., utility supply and generator).

Why: To monitor and trip circuits when earth leakage currents occur on either feeder, protecting motors, drives, and downstream loads from insulation breakdown or ground faults, while ensuring safe changeover between feeders without risking shock hazards, fire, or equipment damage.

Where: In solar inverter output panels and battery bank distribution boards for renewable energy systems in commercial, industrial, or residential setups.

Why: To detect leakage currents from faulty inverter circuits, damaged DC/AC cabling, or degraded battery insulation and disconnect the affected circuit before it causes electric shock, fire hazards, or equipment failure — ensuring personnel safety, system reliability, and compliance with electrical safety standards for renewable installations.