The Siemens SENTRON 3VA1112-1AA36-0AC0 is a 3-pole switch disconnector built in an MCCB-style frame — IEC frame 160, rated 125 A continuous across the full operating temperature range from 40 °C to 70 °C without derating. That flat thermal curve is unusual: most breakers and disconnectors start stepping down above 40 °C, so this part is a clean fit for a warm enclosure or a panel near a heat source where you need the full 125 A at 70 °C. It is a pure disconnector — no overload or short-circuit protection built in (the description flags 'without overload protection w/o short-circuit protection'). That means it is specified as a load-break isolating device downstream of a protective device, or as a maintenance disconnect where the upstream MCCB or fuse already handles fault interruption. The 800 V rated insulation voltage and 690 V AC / 500 V DC operating voltage give it headroom for 400 V and 480 V distribution panels. The auxiliary switches are built in, not an add-on kit — saves a wiring step during panel build.
Mechanical service life is 15,000 operating cycles typical — adequate for a disconnect that sees daily or weekly switching, not a high-cycle application like a welding press. If you need higher cycle life, the MCCB variant (3VA1112-5EE32-0AA0) offers 20,000 cycles but adds thermal-magnetic protection you may not want in a pure disconnect role.
Dimensions: 130 mm high, 76.2 mm wide, 70 mm deep — standard MCCB footprint for the 160 A frame. Front terminals mean the busbar or cable connections land on the face, not the rear, which simplifies wiring in a shallow enclosure. IP40 on the front face is typical for a panel-mounted device; the enclosure itself provides the overall IP rating. Optional motor drive available if remote operation is needed.
Comparison: disconnector vs MCCB variant
The closest peer in the same frame is the 3VA1112-5EE32-0AA0, a full molded case circuit breaker with thermal-magnetic protection (TM220 release, LI characteristic). Same dimensions, same 125 A rating at 40 °C, same front terminal arrangement. The differences: the MCCB variant has a higher mechanical life (20,000 cycles), includes overload and short-circuit protection, and carries a switching capacity class M rating. The 3VA1112-1AA36-0AC0 disconnector is the right choice when you need a load-break isolating switch without integral protection — typically downstream of a separate protective device or in a safety disconnect role where the upstream breaker already coordinates.