What the 160 A rating means for your panel
The GS1LB4 is a TeSys GS fuse switch disconnector body — the guts of a 4-pole, BS-type fused disconnect. It carries a conventional free air thermal current (Ith) of 160 A at 40 °C, which is the continuous current the body can handle in open air without a terminal cover. In real-world panel duty with the terminal cover fitted, the rated operational current (Ie) is 160 A at 400 V and 500 V in AC-23A and AC-23B categories, and 125 A at 690 V AC-23A/AC-23B. The AC-23B rating covers occasional switching of motor loads with inrush — so this body is sized for 160 A motor feeders on 400 V systems where you need a BS fuse carrier. Rated operational power hits 80 kW at 400 V and 110 kW at 500 V or 690 V in AC-23A/AC-23B duty — the higher voltage unlocks the full power capability. If your motor is 75 kW at 400 V, this body has headroom.
Breaking capacity and fault handling
The GS1LB4 is a fuse switch disconnector — it depends on the BS fuses for fault interruption. The body itself is rated for a breaking capacity of 1280 A at 400 V AC-23B and a making capacity of 1600 A at 400 V AC-23B. That making capacity is what the switch contacts can close onto without welding during a fault. Short-circuit withstand rating is 80 kA — that's the prospective fault current the body can survive when backed by appropriately rated BS fuses. The rated short-circuit making capacity (Icm) is 160 kA at 400 V with protection by BS fuses rated at 160 A. This is a robust assembly for high-fault-current industrial panels. Standards compliance covers IEC 60269-1, IEC 60947-3, and IEC 60269-2 — the fuse and switch-disconnector standards. That means the body is tested for coordination with BS fuses under fault conditions.
Mounting, wiring, and environment
Mounts on either a plate or a DIN rail — the TeSys GS family gives you that flexibility for panel layout. Dimensions are 9.4 in wide by 6.4 in tall by 4.8 in deep (240 x 162 x 123 mm), so plan for a 10-inch-wide backpanel bay. Power circuit terminals accept bars or screw terminals for 50 to 95 mm² flexible cable. Tightening torque is 12 N·m (106.2 lbf·in) for both control circuit screw terminals and power circuit bars — use a torque wrench; under-torquing on 95 mm² cable creates a hot spot. IP20 protection with the terminal cover fitted — finger-safe but not splash-proof. Operating temperature range is -20 to 70 °C, which covers most indoor panel environments. Fire resistance of the body is 960 °C and the fuse cover 850 °C per IEC 60695-2-1.
Lifecycle and sourcing
Electrical durability is 1000 cycles in AC-23A/AC-23B and 200 cycles in DC-23A/DC-23B. Mechanical durability is 10,000 cycles. For a fuse switch disconnector that's operated infrequently (maybe a few times a year for lockout/tagout), that's fine — but if you're cycling it daily as a motor switch, consider a contactor instead. Quoted to order against your BOM quantity. Availability and current pricing confirmed at RFQ — no stock-holding claim, but the active lifecycle means lead times are standard for the TeSys GS line.