MCCB for line protection — 100 A, 121 kA SCCR at 240 V
The Siemens SENTRON 3VA1010-4ED42-0HA0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection duty. It carries a rated continuous current Iu of 100 A and delivers a short-circuit breaking capacity of 121 kA at 240 V — the figure that governs fault clearance on low-voltage distribution panels fed from a large transformer. The interrupting rating drops to 75.6 kA at 415 V and 52.5 kA at 440 V, so verify the available fault current at your system voltage before committing the BOM line. At 690 V the rating is 11.9 kA, which limits this variant to lower-fault installations at that voltage. The overcurrent release is a TM210 — thermal-magnetic, fixed-trip, non-interchangeable. That means the 100 A continuous rating is built in; there is no plug-in rating plug to swap for a different amp frame. The breaker includes a shunt trip (STL) for remote opening, specified as 3VA9688-0BL30.
Thermal derating and panel fit
The breaker is rated for 100 A continuously from 40 °C through 50 °C ambient. Above that the thermal curve begins to bite: 96 A at 55 °C, 94 A at 60 °C, 92 A at 65 °C, and 90 A at 70 °C. If the panel internal ambient runs hot — typical in a crowded enclosure with other heat sources — factor the derating into the load schedule. Dimensions are 101.6 mm wide × 130 mm high × 70 mm deep. Front protection is IP40.