What this breaker is and what the ratings mean
The Siemens 3VA1112-6EF42-0AA0-ZD00 is a 4-pole IEC frame 160 molded-case circuit breaker with a breaking capacity class H rating — Icu of 70 kA at 415 V AC. That 70 kA interrupting rating means it can safely clear a fault current up to that level without welding contacts or rupturing the arc chamber, which is the figure that governs whether this breaker holds on a high-fault panelboard or needs an upstream current-limiting fuse. Overload protection is via a TM240 thermal-magnetic trip unit, adjustable from 88 A to 125 A (Ir). Short-circuit magnetic pickup (Ii) is fixed at 5 to 10 times In — so on a 125 A frame, that's 625 A to 1250 A instantaneous trip. The N conductor is unprotected (no overload sensing on the neutral), which is standard for line-side protection on a 3-phase + N system where the neutral is not expected to carry unbalanced load current.
Deployment context and panel integration
This breaker mounts in a standard IEC 160 frame footprint on a DIN rail or panel-mount base. The nut keeper kit included with the DC Power OEM variant secures the busbar connections on the line side — a detail that matters when the breaker is installed in a China-based OEM panel destined for a DC power distribution system. Verify the busbar pitch matches the 4-pole terminal spacing before final torque.
Lifecycle and sourcing reality
For a BOM line that calls out this exact order code, the fit is confirmed by the 125 A TM240 trip curve and the 70 kA @ 415 V breaking capacity. Sourced to order against an RFQ; availability and current pricing are confirmed at quote time through independent distribution.