What this MCCB is and what it does
The Siemens 3VA1180-5ED26-0AA0 is a 2-pole SENTRON molded case circuit breaker (MCCB) rated for line protection — the primary role of an MCCB in a distribution panel is to protect downstream cables and equipment from overloads and short circuits, with the thermal-magnetic TM210 release handling both curves. Rated continuous current Iu is 80 A, and the adjustable Ir matches that same 80 A maximum, so this breaker is sized for a 80 A feeder or branch circuit. The interrupting ratings are the headline: 187 kA at 240 V and 121 kA at 415 V — those figures mean it can safely clear a fault up to that level without welding contacts or rupturing the case, which is critical for high-fault-capacity industrial panels where upstream transformers can deliver massive short-circuit current.
Thermal derating and real-world fit
This breaker holds its full 80 A rating up to 50 °C ambient — at 55 °C it derates to 78 A, at 60 °C to 77 A, and at 70 °C to 74 A. That means in a warm panel (say, 55 °C inside the enclosure) you lose only 2 A of headroom; the TM210 release still provides reliable overload protection. The 70 mm depth and 50.8 mm width (2.8 in × 2 in) fit the standard SENTRON 3VA mounting footprint, so it drops into existing 3VA panel layouts without re-drilling. IP40 on the front means it's protected against solid objects over 1 mm — fine for a closed panel, but not for washdown areas.
Key ratings at a glance
Rated insulation voltage Ui is 500 V, and max rated operational voltage with DC is 250 V — so it's suitable for 480 V AC distribution and 250 V DC circuits. The adjustable short-circuit release Ii is fixed at 800 A (both min and max), meaning the magnetic trip threshold is non-adjustable on this TM210 variant. Latching endurance is 20 000 operations — adequate for a distribution breaker that sees infrequent switching. Power loss at rated current is 12.8 W maximum, which matters for thermal calculations in a sealed enclosure.