The Siemens SENTRON 3VA1120-5EE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) designed for line protection, carrying a 20 A continuous rating at 40 °C and a TM220 thermal-magnetic overcurrent release. Its interrupting capacity hits 187 kA at 240 V and 121 kA at 415 V — numbers that put it squarely in the high-fault-current panel class, sized for main or feeder duty where upstream SCCR demands serious headroom.
Ratings and what they mean for fit
The 20 A rating holds flat from 40 °C up to 55 °C, then derates to 19 A at 60 °C and above — so in a warm enclosure you lose only 1 A, not a full trip threshold. The TM220 release gives a fixed thermal curve with magnetic pickup around 10x In, typical for motor or general distribution branch circuits where short-circuit coordination, not nuisance tripping, is the priority. Rated insulation voltage is 800 V, and the interrupting ratings step down as voltage climbs: 75.6 kA at 440 V, 17 kA at 500 V and 690 V. That 17 kA at 690 V still covers most industrial 690 V distribution, but if your fault current at that voltage exceeds 17 kA, this breaker won't hold — check the point-on-wave coordination study before committing the BOM line. Power loss is 12 W maximum at rated load — negligible for thermal budgeting in a standard enclosure, but worth noting if you're packing multiple breakers into a sealed stainless box with no forced ventilation.
Lifecycle and sourcing
The lifecycle stage is listed as current — meaning Siemens still actively manufactures and supports this order code. No end-of-life notice or successor has been issued. That's one less SKU to worry about for the next five years.
Physical fit and panel integration
Footprint is 101.6 mm wide by 130 mm tall by 70 mm deep — a 4-inch-wide body that fits standard Siemens 3VA panel-mounting patterns. IP40 on the front means it's protected against tools and wires >1 mm, but not against dripping water; keep it inside a rated enclosure.