The Siemens 3VA1150-4ED32-0AA0-ZD00 is a 3-pole IEC frame 160 molded case circuit breaker (MCCB) with a 50 A fixed thermal-magnetic trip unit (TM210). The fixed overload protection (Ir = 50 A) and fixed short-circuit pickup (Ii = 10 × In, so 500 A) mean the trip settings are not field-adjustable; you select this variant when the load is known and fixed, avoiding tamper risk or mis-set dials on a production line.
Where it fits and how it is used
The 'nut keeper kit for DC Power OEM in China' suffix (ZD00) indicates it was configured for a specific DC power OEM application; the base breaker itself is a standard line-protection device for cable, busbar, and non-motor loads. The TM210 curve is thermal-magnetic: the thermal element handles sustained overloads (cable heating), the magnetic element clears short-circuits instantly above the pickup threshold.