What this breaker is and what the ratings mean
The Siemens 3VA1110-3EE42-0AA0-ZD00 is a 4-pole IEC frame 160 molded case circuit breaker from the 3VA1 series, with a TM220 thermal-magnetic trip unit and ATFM (Adjustable Thermal Fixed Magnetic) overload and short-circuit protection. The In=100A continuous rating and Ir adjustable from 70A to 100A let you dial in the overload pickup to match the cable or load — common for motor branch circuits or feeder protection where the exact FLA lands inside that window. The Ii fixed at 10 x In (1000A) means magnetic trips happen fast on hard faults, but won't nuisance-trip on moderate inrush. Breaking capacity class N delivers Icu=25kA at 415V AC — that's the maximum fault current the breaker can safely interrupt without welding or rupturing. For a 415V distribution board with available fault current under 25kA, this breaker coordinates cleanly downstream of a current-limiting fuse or upstream breaker. The N conductor is unprotected on this variant, so it tracks the phase protection but doesn't have its own overload element — standard for balanced 3-phase loads where the neutral carries only imbalance current.
Where it fits in the panel
This breaker mounts on a DIN rail or can be screw-fixed to a backplate in a standard distribution or motor control center enclosure. The 4-pole format with unprotected neutral suits TN or TT systems where the neutral is solidly earthed and doesn't need its own trip. The nut keeper kit for DC Power OEM in China suggests this specific variant was configured for a DC power OEM application — verify the DC rating curve if using on DC circuits, as the thermal-magnetic trip is calibrated for AC 50/60 Hz waveforms.