The GS1S4 is a 4-pole fuse switch disconnector body from the TeSys GS series, rated for DIN-rail mounting and accepting T3-size DIN fuses. It's the core switching element for a fused disconnect — you add the operating handle (external right-side or frontal) and fuse links to complete the assembly. The part carries a conventional free-air thermal current (Ith) of 630 A at 40 °C, and its rated operational current varies by duty: 630 A at 400 V in AC-23A/B, 500 A at 500 V in AC-23A/B, and 400 A at 690 V in AC-23A/B. For DC applications with poles not juxtaposed, it's rated 630 A at 440 V in DC-23A/B.
The breaking capacity of 5040 A at 400 V AC-23B and making capacity of 6300 A at 400 V AC-23B define its fault-interruption capability under motor-switching duty (AC-23B covers occasional switching of individual motors). The rated short-circuit making capacity (Icm) is 100 kA at 400 V when protected by gG fuses rated 630 A — that's the peak let-through the switch can close onto without welding. Rated impulse withstand voltage (Uimp) of 12 kV and insulation voltage (Ui) of 1000 V AC give it headroom for 690 V systems. Electrical durability is 1000 cycles in AC-23A/B and 200 cycles in DC-23A/B; mechanical durability is 8000 cycles. These numbers tell you this is a robust industrial disconnect meant for infrequent but high-integrity switching — not a daily-use contactor.
Designed to IEC 60269-1, IEC 60269-2 (fuse standards), and IEC 60947-3 (switch-disconnector standard). The fuse cover passes the glow-wire test at 1562 °F (850 °C) and the body at 1760 °F (960 °C) per IEC 60695-2-1. IP20 protection with terminal cover fitted — suitable for enclosed panel use, not washdown environments. Protective treatment is TH (tropicalized) for humid environments.