What this part is and what it does
The Siemens SENTRON 3VA1110-1AA42-0HH0 is a 4-pole switch disconnector in an MCCB (molded case circuit breaker) physical design, rated for 100 A continuous current — and that rating holds flat across the entire operating temperature range from 40 °C up to 70 °C, so no derating curve to chase when the panel runs hot. It is built for isolation and switching duty, not overcurrent protection: no overload or short-circuit trip elements inside. The part carries a shunt trip release (STL) for remote opening on a 12–30 V DC or 24 V AC signal, plus two auxiliary switches and one trip alarm switch (HQ configuration) for status feedback back to a PLC or annunciator.
Where it fits in the panel
The 3VA1110-1AA42-0HH0 uses a front-terminal busbar connection for the main circuit, which means it lands on a busbar stack rather than individual cable lugs — standard for MCCB-style switch disconnectors in distribution panels. The 70 mm depth keeps it within the envelope of most 160 A frame SENTRON breakers, so it shares the same mounting footprint and busbar riser kit. IP40 on the front face means it is protected against tools and wires larger than 1 mm, but the rest of the device is open to the enclosure environment — install it in a panel that provides the overall IP rating the site demands.
Key ratings and what they mean for the buyer
Rated operating voltage is 690 V AC and 600 V DC, with an insulation voltage of 800 V — that gives headroom for 480 V and 600 V class systems without pushing the dielectric limits. The 100 A continuous rating is flat from 40 °C to 70 °C, so a panel that hits 60 °C in summer still carries the full 100 A without needing a larger frame. Maximum power loss is 38 W — relevant for thermal budgeting inside a sealed enclosure. Mechanical service life is 15,000 operating cycles typical, which is adequate for a switch disconnector used in infrequent isolation service (not daily motor starting). The shunt trip (STL) coil is rated 12–30 V DC / 24 V AC 50/60 Hz — a wide DC range that covers 24 V nominal control supplies with margin. The three CO contacts (two aux + one trip alarm) give the control system discrete feedback for open/closed and tripped states.