Breaking capacity and what it means for your fault level
ETU350 trip unit and N-conductor protection
The electronic trip unit is an ETU350, which gives adjustable long-time, short-time, and instantaneous protection curves. The N-conductor protection is configurable: OFF, 50 %, or 100 % of the phase current — useful on 4-wire systems where you need to match the neutral to the load balance. No undervoltage release or shunt trip is fitted as standard; those are field-addable accessories if your circuit demands remote tripping.
It mounts via screw terminals onto a backplate or DIN-rail adapter (the SENTRON 3VA range uses a common mounting footprint). If it goes into a wet or dusty panel, the enclosure provides the IP rating, not the breaker itself.