Siemens 3VA1120-3EF36-0CH0 — SENTRON 3-pole MCCB, 20 A, line protection
Its interrupting capacity scales with system voltage: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 10.5 kA at 690 V — so at 415 V it clears a 52.5 kA fault without upstream coordination failure, which is the figure that governs most industrial panel SCCR compliance. No communication function, no phase failure detection, no ground fault monitoring — this is a pure line-protection device, not a power monitor.
Thermal derating and mechanical endurance
Rated continuous current holds at 20 A from 40 °C through 50 °C ambient; above that it derates linearly to 18 A at 70 °C. The breaker is rated for 15 000 mechanical operations — that is the latching endurance figure, so it is sized for moderate switching duty in a distribution panel, not for continuous motor starting.
The 76.2 mm width is a standard 3-pole MCCB footprint — it fits the same DIN-rail or panel-mount cutout as other SENTRON 3VA1 3-pole units. The 70 mm depth leaves clearance for rear-access busbars in a typical 200 mm deep enclosure.