The Siemens 3VA1150-3ED42-0AA0-ZD00 is a 4-pole IEC frame 160 molded case circuit breaker with a 50 A thermal-magnetic trip unit (TM210).
The overload protection is fixed at Ir = 50 A, and the short-circuit pickup is fixed at Ii = 10 × In (500 A). This is a non-adjustable TM210 curve — the trip characteristics are set at the factory, so it's a straight swap-in for a BOM line that already calls for a 50 A fixed-trip breaker. The N conductor is unprotected on this variant, and the unit includes a nut keeper kit for DC Power OEM installations in China.