D-curve 4-pole MCB for motor and transformer branch protection
Its D-curve allows a brief magnetic-trip delay — typically 10–20× rated current — so it won't nuisance-trip on startup surge while still providing short-circuit protection. Rated 400 V AC (440 V max multi-phase), it breaks 10 kA per IEC 60898-1 or 15 kA per IEC 60947-2, and 15 kA at 60 V DC per IEC 60947-2. The 4-pole layout with switched neutral (3P+N) means the neutral is opened and closed with the phases, useful for TN-S or TT systems where isolating all live conductors is required.
Breaking capacity across standards
This breaker carries three distinct interrupting ratings depending on the applicable standard: 10 kA per EN 60898-1 (household-type), 15 kA per IEC 60947-2 (industrial), and 5 kA per UL 1077 / CSA C22.2 No. 235. For DC circuits, it is rated 15 kA at 60 V (max 72 V). The dual rating means it can be specified in both residential and industrial panels — the 15 kA IEC figure gives headroom for higher fault-current locations. The D-curve and 4-pole format make it a common choice for branch circuits feeding motor control centers or small transformers where neutral switching is required.
Installation and environmental fit
Snap-on DIN rail mounting, any orientation. Depth 76 mm (installation depth 70 mm), width 72 mm (4 MW), height 90 mm. IP20 with conductors connected; pollution degree 3 (conductive or dry non-conductive pollution). Operating temperature range -40 to 75 °C, with humidity limits up to 95% at 55 °C. Terminal design allows combined top/bottom feed — supply cord position is arbitrary. Sealable for tamper-proof applications. Halogen-free and silicon-free construction.