What it is and what it does
The Siemens SENTRON 3VA1120-6EF46-0AA0 is a 4-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a continuous 20 A at 40 °C and delivers a 220 kA interrupting capacity at 240 V — enough to handle high-fault utility feeds or transformer secondaries without cascading upstream. The TM240 overcurrent release combines thermal-magnetic trip elements for overload and short-circuit protection. Insulation voltage is rated 800 V, so the breaker can be applied in 480Y/277 V or 600 V delta systems with margin.
Breaking capacity across voltage levels
Interrupting rating drops as voltage rises: 154 kA at 415 V, 121 kA at 440 V, and 17 kA at 500 V and 690 V. At 500/690 V the rating is still substantial for most industrial loads, but the 220 kA at 240 V is the headline figure for high-fault commercial services.
Thermal derating and ambient range
The breaker holds 20 A from 40 °C through 55 °C without derating. At 60 °C and 65 °C it drops to 19 A; at 70 °C it stays at 19 A. Operating ambient spans -25 °C to 70 °C, storage from -40 °C to 80 °C. For panels near ovens or outdoor enclosures in direct sun, the 19 A floor at 70 °C is the safe continuous limit.
Panel fit and integration
Dimensions are 101.6 mm wide, 130 mm tall, 70 mm deep. Four-pole MCCBs of this width typically mount on a DIN rail or bolt directly to a panel backplate. The front face carries IP40 protection — suitable for enclosed distribution boards, not for washdown environments.