Lifecycle and Sourcing Reality
The GS1NB3: This part is available through independent distribution channels.
Rated Performance and Duty
Rated 250 A at 400 V in AC-23B duty — this is the motor-switching category per IEC 60947-3, meaning it handles high inrush currents from motor starts up to that current level. The same 250 A rating holds at 500 V and 690 V (with terminal cover) in AC-23A and AC-23B. Breaking capacity is 2000 A at 400 V AC-23B; making capacity is 2500 A at the same condition. The short-circuit making capacity (Icm) reaches 250 kA at 400 V when protected by BS fuses rated at 250 kA. Rated operational power spans 132 kW at 400 V AC-23A/B up to 220 kW at 690 V AC-23A/B. The conventional free-air thermal current (Ith) is 250 A at 104 °F (40 °C).
Standards, Protection, and Environment
Designed to IEC 60947-3 (switch-disconnector standard), IEC 60269-2 (fuse requirements), and IEC 60269-1 (general fuse rules). The body achieves IP20 protection with the terminal cover fitted per IEC 60529 — suitable for enclosed panel mounting where incidental finger contact is prevented. Fire resistance tested to IEC 60695-2-1: the body withstands 1760 °F (960 °C) and the fuse cover 1562 °F (850 °C). The rated impulse withstand voltage (Uimp) is 8 kV, and the rated insulation voltage (Ui) is 750 V AC 50/60 Hz. Operates in ambient temperatures from -4 °F to 158 °F (-20 °C to 70 °C). Protective treatment is TH (tropicalized). Mechanical durability is rated at 10,000 cycles; electrical durability is 1000 cycles in AC-23A/B and 200 cycles in DC-23A/B.
Physical Integration and Connections
Dimensions: 5.7 in (146 mm) depth, 9.8 in (250 mm) width, 7.7 in (195 mm) height. Mounting support is plate or rail — the body can be panel-mounted or DIN-rail mounted depending on the enclosure layout. Power circuit terminals accept bars or screw terminals for flexible cable from 0.1 to 0.4 in² (95 to 240 mm²). Tightening torque is 221.3 lbf·in (25 N·m) for both control and power circuit screw terminals. Accepts BS-type fuses in sizes, B3. The operating handle can be mounted externally on the right side or frontally. Three-pole configuration (3P).