The Siemens 3VA1150-3EF42-0AA0-ZD00 is a 4-pole IEC frame 160 molded case circuit breaker rated at 50 A continuous current, with a 25 kA interrupting capacity at 415 V (breaking capacity class N). It carries the TM240 thermal-magnetic trip unit with an ATAM (Adjustable Thermal, Adjustable Magnetic) adjustment range: overload protection (Ir) is settable from 35 A to 50 A, and short-circuit protection (Ii) from 5 to 10 times In. This variant is configured for DC Power OEM applications in China.
The TM240 trip unit with ATAM adjustment gives the panel builder flexibility: Ir from 35 A to 50 A allows fine-tuning for cable or load protection without swapping the breaker, while Ii at 5–10× In sets the magnetic trip threshold for motor-start inrush or high-impedance faults. The unprotected N conductor means the neutral is not switched or monitored by the breaker — confirm the system's neutral earthing arrangement before specifying.
Deployment Context
The nut keeper kit aids secure fastening in high-vibration environments like DC power OEM enclosures.