The Fast-cutting Mechanism Of Drop-out Fuses

The core component of the drop out fuse element fuse tube contains a tin-copper alloy or silver-copper alloy fuse element. During normal circuit operation, the fuse element temperature remains within the material's permissible working range. When an overload current flows through the fuse element, the resistive heating power increases according to the I²R law, causing the fuse element temperature to exceed its melting point within milliseconds. The fuse element of the drop out fuse in transformer employs a multi-section variable-cross-section design. The narrow neck section reaches melting temperature first. Once the metal liquefies, the conductive path is interrupted, confining the fault current within the fuse tube.

Upon melting, the fuse generates high-temperature gases and metal vapors, causing the internal pressure to surge to several atmospheres. The upper contact of the drop out fuse price is connected to the fuse tube via a duckbill clamp. The pressure shock causes the clamp to disengage, allowing the fuse tube to rotate downward under the combined force of gravity and spring tension. The entire drop sequence completes within 0.05 seconds. After separating from the conductive rod, the fuse tube creates a distinct gap. This mechanical displacement transforms electrical isolation into a visible physical disconnection, allowing maintenance personnel to intuitively assess the operational status of the device.