DC-rated miniature circuit breaker, 25 A C-curve, 2 poles
The MGN61852 is a Schneider Electric Multi9 C60H-DC miniature circuit breaker — a 2-pole, 25 A thermal-magnetic unit with a C-curve trip characteristic, built specifically for DC circuits. Rated 25 A at 50 °C per EN/IEC 60947-2, so the 25 A mark is the continuous current at elevated panel temperature — no derating guesswork needed if your enclosure stays under that ambient. Breaking capacity is the headline here: 20 kA Icu at 220 V DC and 250 V DC, 10 kA at 440 V DC, and 6 kA at 500 V DC. For a 250 V DC bus — common in telecom, UPS, or solar combiner panels — the full 20 kA SCCR is available. At 500 V DC the 6 kA rating still covers most industrial control circuits. The IP20 finger-safe front and IP40 inside the modular enclosure are standard for panelboard use — not rated for washdown, but fine inside a sealed cabinet. Padlockable toggle for lockout/tagout, with ON/OFF indication visible through the enclosure door.
Unlike AC breakers that rely on a zero-crossing to extinguish the arc, DC breakers must stretch and cool the arc without a natural current zero. The C60H-DC's arc chamber and contact materials are designed for that — the 20 kA Icu at 250 V DC is a real DC rating, not an AC-to-DC conversion. For a 48 V or 125 V DC control bus this breaker is oversized in voltage, which is fine; for a 500 V DC drive bus, the 6 kA breaking capacity is the limit to respect. Insulation voltage rated 500 V DC (Ui), so the internal creepage distances hold up at that level. The tunnel terminals accept up to three 1 mm² flexible conductors per pole for daisy-chaining, or a single 25 mm² for the main feed. Tightening torque 2.5 N·m top and bottom. Wire strip length 14 mm — standard for this terminal family.