What the ratings mean for fit
The GS1VBR4 is a fuse switch disconnector body — the base unit that accepts BS-type fuse links (size D1) to make a fused disconnect for motor or distribution circuits. It is rated 1250 A conventional free air thermal current (Ith) at 40 °C, which is the continuous current the body can carry in open air without additional enclosure derating. In AC-23A duty (switching motor loads or other high-inrush loads), the rated operational current is 1000 A at 400 V and 800 A at 500 V, with a corresponding power rating of 560 kW at 400 V. The 4-pole configuration handles three-phase plus neutral or two independent circuits. Breaking capacity is 10,000 A at 400 V AC-23B, and making capacity is 8,000 A at the same voltage — the body can close onto and interrupt fault currents up to those levels when fitted with the correct BS fuse links. The short-circuit making capacity with protection by BS fuses is 1250 kA at 400 V, limited by the fuse rating.
Panel integration and mounting
Mounts on a plate or rail — the body dimensions are 14.3 in deep, 26.8 in wide, and 17.05 in tall, so it needs a back panel at least 27 in wide by 18 in tall for clearance. Power circuit connections accept up to 185 mm² flexible cable on screw terminals or 100 mm² on bars, with a tightening torque of 44 N·m on the power circuit. IP20 with the terminal cover fitted — finger-safe but not washdown-rated; install inside a cabinet. The body is rated for operation from -20 °C to 70 °C and storage from -40 °C to 80 °C, with TH protective treatment for tropical humidity.
Lifecycle and sourcing posture
Compliance with IEC 60269-1, IEC 60269-2, and IEC 60947-3 means the body meets the international standards for fuse systems and switch-disconnectors. Fire resistance is 960 °C for the body and 850 °C for the fuse cover per IEC 60695-2-1.