What this breaker is and what it does
The Siemens 3VA1225-4EE32-0AA0-ZD00 is a 3-pole IEC frame 250 molded-case circuit breaker rated for line protection with a TM220 thermal-magnetic trip unit. It carries an interrupting capacity of 36 kA at 415 V (breaking capacity class S), which means it can safely clear a fault up to that level without upstream damage — a key figure for panel coordination studies and SCCR compliance.
Overload and short-circuit settings
The TM220 trip provides adjustable overload protection (Ir) from 175 A to 250 A, with a fixed short-circuit pickup (Ii) at 10 × In (2,500 A). This setup suits feeder or large motor branch circuits where the load current is known and coordination with downstream devices is needed.