Motor protection breaker with ETU860M trip unit
The Siemens 3VA2325-5MQ32-0DJ0 is a 3-pole IEC frame 400 circuit breaker with class M breaking capacity — 55 kA at 415 V — fitted with an ETU860M electronic trip unit for motor protection. The LSIG protection profile covers long-time (overload), short-time, instantaneous, and ground-fault functions, with overload pickup adjustable from 100 A to 250 A. Short-circuit protection is set via Isd from 1.2 to 15 × In, with a fixed instantaneous pickup at 15 × In. Ground-fault protection is switchable, adjustable from 0.2 to 1 × In with a time delay of 0.05 to 0.8 s. This breaker includes an undervoltage release (UVR) rated 208–230 V AC 50/60 Hz, two auxiliary switches (HP), and one trip alarm switch (HP). The UVR ensures the breaker trips on loss of control voltage — standard for motor starter circuits where unintended restart after a power dip must be prevented.
Deployment context
The 3VA2 frame mounts on a DIN rail or panel plate in a motor control center or distribution board. The ETU860M trip unit communicates via the internal bus for power monitoring and parameterization — useful for coordinated motor protection schemes where selective coordination with downstream contactors and overload relays is required.