MCCB with ETU350 trip unit and shunt trip
The Siemens 3VA2010-5HN42-0HJ0 is a 4-pole IEC frame 100 molded case circuit breaker rated for 100 A continuous current with a 55 kA interrupting capacity at 415 V (breaking capacity class M). It carries an ETU350 electronic trip unit configured for LSI protection — long-time (Ir adjustable 40–100 A), short-time (Isd 1.5–10 x Ir), and instantaneous (Ii fixed at 12 x In). The N-conductor protection is field-adjustable to OFF, 50%, or 100% of phase pickup. A factory-installed shunt trip (left side, 24 V AC 50/60 Hz / 24–30 V DC) and space for up to two auxiliary switch blocks are included.
The ETU350 LSI curve gives selective coordination flexibility: the short-time pickup and delay bands let you cascade downstream breakers while keeping the main breaker closed through a temporary fault. The 100 A frame with Ir down to 40 A means it covers a wide motor or feeder range from a single frame size.
Integration notes
The nut keeper kit (included) retains the mounting screws during installation — useful for tight enclosures where dropped hardware is a delay. The shunt trip occupies the left accessory slot; verify the control voltage matches the 24 V AC/DC supply before energizing. Auxiliary switch blocks (up to two) plug into the right-side slots without removing the breaker from the panel.