What this breaker is and what it does
The Siemens 3VA1116-5EE42-0AA0-ZD00 is a 4-pole IEC frame 160 circuit breaker rated for line protection, carrying a 160 A continuous current rating (In) and a 55 kA ultimate breaking capacity (Icu) at 415 V AC — class M breaking capacity. That means it can safely interrupt fault currents up to 55 kA without welding its contacts or cascading the fault upstream, which is the spec that governs whether this breaker holds on a high-fault panelboard or needs a current-limiting upstream device. The TM220 thermal-magnetic trip unit gives adjustable overload protection (Ir) from 112 A to 160 A, matching the conductor or load ampacity, and a fixed short-circuit pickup (Ii) at 10× In, so it clears bolted faults fast while riding through motor inrush. The N conductor is unprotected — this is a 3-pole + N configuration where the neutral is switched but not monitored for overload, typical for line-side distribution where the neutral is sized to carry only the unbalanced return current.
Where it fits in the panel
This breaker mounts on a DIN rail in a standard distribution or motor control center enclosure. The 4-pole footprint occupies four module widths on the rail; the nut keeper kit (included per the order-code suffix) is a detail for the DC Power OEM variant destined for China — it holds the terminal nuts captive during assembly, saving a hand on the line.