The Siemens 3VA1120-3EE32-0AA0-ZD00 is a 3-pole IEC frame 160 molded case circuit breaker (MCCB) with a 20 A rated current and a 25 kA ultimate breaking capacity (Icu) at 415 V, placing it in breaking capacity class N. The TM220 thermal-magnetic trip unit gives adjustable overload protection from 14 A to 20 A (Ir) and a fixed short-circuit pickup at 16 x In (320 A).
The adjustable Ir (14–20 A) lets you match the breaker to the actual continuous load current, not just the fixed In, which helps avoid nuisance tripping on lightly overloaded circuits.