The Siemens 3VA1150-3EF32-0AA0-ZD00 is a 3-pole IEC frame 160 circuit breaker rated at In=50A with a breaking capacity class N, delivering Icu=25kA at 415 V. Overload protection (Ir) is adjustable from 35 A to 50 A via the TM240 thermal-magnetic trip unit; short-circuit protection (Ii) is set at 5 to 10 times In. The unit includes a nut keeper kit and is configured for DC Power OEM applications in China.
The adjustable overload range (35–50 A) lets you match the thermal trip to the actual load current within that band — set Ir to the motor FLA or feeder load, not to In. The short-circuit pickup at 5–10× In means the magnetic trip responds to fast-rising fault currents; for a 50 A breaker, that's 250–500 A instantaneous.
Deployment Context
The nut keeper kit is specific to the DC Power OEM variant destined for China — verify the kit is present if you are replacing an existing unit in that application.