What this frame is — and what it isn't
The C63F4 is a ComPacT NSX630F basic frame — a 630 A at 40 °C, 4-pole air circuit breaker chassis that ships without a trip unit. You specify the protection module (electronic or thermal-magnetic) separately, which means this single frame covers distribution, motor, or generator protection depending on the plug-in trip unit you pair it with. Rated 690 V AC operational voltage with an 800 V insulation rating, and breaking capacity at 36 kA Icu at 380/415 V AC (EN/IEC 60947-2) or 85 kA at 240 V AC (UL 508). The 4-pole, fixed-mount format with front front connections suits panelboard or switchboard integration where you need a bare chassis and want to select protection later.
Breaking capacity across voltage — the so-what
The C63F4 carries multiple interrupting ratings because the arc extinguishes differently at each voltage. At 240 V AC (UL 508) it clears 85 kA — a strong number for a 630 A frame in North American panelboard duty. At 480 V AC the rating drops to 35 kA (UL 508), still adequate for most industrial distribution. Under IEC 60947-2 the 36 kA Icu at 380/415 V AC is the headline European rating; the 25 kA Ics at the same voltage means the breaker can be reclosed after clearing a fault at that level without immediate replacement. The 10 kA Icu at 660/690 V AC confirms it handles high-voltage low-fault-current applications like mining or marine switchgear. Match your system's available fault current and voltage to the appropriate rating — don't assume the highest number applies at your voltage.
Fixed-mount on a backplate — no DIN-rail clip. Dimensions: 255 mm high, 185 mm wide, 110 mm deep. The 45 mm connection pitch and 4-pole layout with neutral on the left are standard for panelboard busbar drilling. Front connections top and bottom simplify busbar or cable routing. IP40 front face, IK07 impact resistance. Pollution degree 3 (IEC 60664-1) means it tolerates conductive dust in non-condensing environments — typical for a switchboard enclosure, not a clean room.
Mechanical endurance is 15,000 cycles; electrical endurance varies with load — 8,000 cycles at 440 V AC at half rated current, 2,000 cycles at full rated current and 690 V AC. Impulse withstand voltage 8 kV. Class II insulation on the front face means no protective-earth connection needed on the operator-facing side.