Interrupting capacity and thermal-magnetic release
The Siemens SENTRON 3VA1050-4ED32-0CC0 is a 3-pole molded case circuit breaker (MCCB) rated for 50 A continuous current at 40 °C, with a TM210 thermal-magnetic overcurrent release. Its interrupting capacity is 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V — the 121 kA figure at 240 V is the headline number that determines fault-clearing capability at the service entrance or main distribution panel. The TM210 release is a fixed thermal-magnetic trip unit with no phase-failure detection and no communication function. The breaker carries 50 A through 50 °C, then derates to 48 A at 55 °C, 47 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C — relevant for panel builders who need to account for internal enclosure temperature rise.
Undervoltage release and auxiliary contacts
This MCCB includes an undervoltage release (UVR) as the auxiliary release design, which trips the breaker when supply voltage drops below a threshold — typical for motor branch circuits where a loss-of-voltage event must disconnect the load to prevent automatic restart. The integrated auxiliary trip is order code 3VA9608-0BB24. Two auxiliary switches (HQ version) are built in, providing status feedback for the breaker's open/closed and tripped states. The front face carries IP40 protection, so the breaker is suitable for installation inside a panel with a sealed door; it is not rated for outdoor or washdown environments.