What the D curve and 6 A rating mean for your panel
The MGN60521 is a C60N miniature circuit breaker from the Multi9 range, rated 6 A at 50 °C with a D tripping curve. The 6 A thermal element protects the downstream cable against sustained overloads; the magnetic element clears short-circuits fast enough to keep the fault energy within the cable's withstand rating. Breaking capacity is 20 kA Icu at 240 V AC phase-to-phase, 10 kA at 415 V, and 6 kA at 440 V — all conforming to EN/IEC 60947-2. For a 240 V distribution board fed from a transformer with a prospective short-circuit current under 20 kA, this breaker provides full discrimination upstream.
Occupies 4 modules of 9 mm pitch (36 mm total width). The 73 mm depth and 81 mm height fit standard distribution enclosures. Pollution degree 3 per EN/IEC 60947-2 means it's rated for the conductive-dust environment inside a typical industrial panel.
IP20 finger-safe protection on the front face. Storage temperature range -40 to 80 °C, operating ambient -30 to 70 °C. The D curve and 2-pole configuration make it a direct fit for 240 V split-phase or 415 V phase-to-phase motor branch circuits where a C curve would trip on inrush.