The Siemens 3VA1216-4GE42-0AA0-ZD00 is a 4-pole IEC frame 250 circuit breaker rated for line protection with a TM220 thermal-magnetic trip unit. Its breaking capacity class S delivers Icu=36kA at 415V, which means it can safely interrupt fault currents up to 36,000 amps without welding or rupturing — enough for most industrial distribution panels downstream of a transformer. The overload protection is adjustable Ir=112A…160A, so you set the continuous current to match the load, not the breaker frame. Short-circuit protection is fixed at Ii=10 x In (1600A), a standard instantaneous pickup for motor and feeder circuits.
What the ratings mean for fit
The 36kA Icu at 415V is the ultimate breaking capacity — the breaker can clear one fault at that level and still be serviceable. For selectivity studies, the service breaking capacity (Ics) is typically 100% of Icu on this class S frame, so coordination with downstream breakers is straightforward. The 4-pole configuration with 100% N conductor protection means the neutral is switched and protected at the same rating as the phases, required for 4-wire systems where neutral current can approach phase current (e.g., harmonic-rich loads or mixed single-phase/three-phase panels).
Deployment context
This breaker mounts on a DIN rail or panel-mount base inside a standard industrial enclosure. The nut keeper kit for DC Power OEM in China indicates it was ordered with a specific accessory for DC-side applications — verify the kit is included if the BOM calls for it.