Plant electricians at a hot‑rolling mill count on this relay to guarantee safe energisation of the strip‑draw frames during start‑up. Positioned inside the drive‑control cabinets, it switches the DC power that feeds the roll‑drive motors, tension‑control loops and slab‑transfer conveyors. When a fault such as an overload or a short‑circuit develops, the relay isolates the affected circuit, preventing damage to the steel strip and the heavy‑duty drive gear. Its contacts are wired to the plant’s supervisory system, so operators receive a clear visual indication of a fault and can reset the circuit after inspection. Because steel‑plant environments are hot, dusty and subject to vibration, the relay’s mechanical design tolerates those conditions while providing reliable, repeatable switching for the furnace‑feed conveyors and the cooling‑line rollers. Plant operators in other heavy‑process facilities use the same device for similar motor‑control tasks, benefiting from its straightforward integration into existing control panels. When a sudden overload occurs on the slab‑transfer conveyor, the relay opens the DC circuit, protecting the drive and preventing a costly line stoppage.