The Schneider Electric MGN60898 is a C60N miniature circuit breaker from the Multi9 range, rated 40 A at 50 °C with a C-curve trip characteristic.
The 3-pole footprint takes 6 module pitches (54 mm wide), so it occupies three adjacent slots on the rail. Tunnel terminals accept 1.5 to 35 mm² rigid or flexible wire; strip length is 14 mm, torque to 3.5 N·m. IP20 finger-safe front, pollution degree 3 rated, so it handles the dusty, humid environment inside a typical industrial cabinet without derating.
Rated operational voltage is 440 V AC 50/60 Hz, with service breaking capacity (Ics) at 75 % of Icu: 15 kA at 240 V, 7.5 kA at 415 V, 4.5 kA at 440 V. Magnetic tripping threshold is 8.5 x In ±20 % — so on a 40 A breaker, the instantaneous magnetic trip fires between about 272 A and 408 A. That's a tight window for a C-curve, good for motor-starting inrush without nuisance trips on moderate inductive loads. Electrical endurance is 10,000 cycles; mechanical is 20,000. Suitability for isolation is marked, with a contact position indicator and ON/OFF local signaling.