What this MCCB is and what it does
The Siemens 3VA1120-6ED46-0AA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection — meaning it sits on the incoming feeder or main distribution to guard against overloads and short circuits before downstream branch breakers see the fault. It carries a 20 A continuous rating at 40 °C ambient, derating to 19 A at 60 °C and above, so it holds its rating across most panel environments without a big temperature penalty. The 4-pole configuration handles three-phase plus neutral switching — common for 3-phase distribution where you want to isolate the neutral as well.
Breaking capacity — the real headroom
The headline number is 220 kA at 240 V, which drops to 154 kA at 415 V and 121 kA at 440 V. At 500 V and 690 V it still holds 17 kA. That means this breaker can be installed upstream of a high-fault transformer or busway without worrying about cascading failure — the SCCR is high enough to let it clear a bolted fault before the arc flash energy climbs. The TM210 overcurrent release is a thermal-magnetic trip unit — thermal for overload protection, magnetic for short-circuit. No electronic adjustments, no communication module, no ground-fault monitoring. It's a fixed-trip breaker for straightforward line protection where you don't need selectivity tuning.
Panel fit and dimensions
The breaker measures 130 mm high, 101.6 mm wide, and 70 mm deep — a standard MCCB footprint that drops into a SENTRON or third-party distribution panel without re-drilling the mounting plate. Front IP40 protection means it's fine for a clean indoor panel; not rated for washdown or outdoor exposure.