Switch disconnector, not a breaker — what that means for your BOM
The Siemens 3VA1112-1AA32-0JA0 is a SENTRON 3VA1 switch disconnector in MCCB-style hardware — same 160 A frame, same 3-pole footprint — but it carries no overcurrent release and no short-circuit protection. It is a load-break disconnect rated for 125 A continuous current (Iu) at up to 690 V AC 50/60 Hz or 500 V DC. The absence of a trip unit means this part is specified where the upstream feeder already provides protection and the panel needs a visible-break isolation point with a shunt trip for remote emergency-off.
Shunt trip and auxiliary release — the remote-trip path
The shunt trip occupies the auxiliary release slot and lets a remote signal — from an E-stop button, a safety PLC output, or a fire-alarm relay — open the disconnect without an operator at the handle. The disconnect accepts an optional motor drive (product extension marked as available), which allows remote motorized open/close for automated sequences.
Panel fit and connection — front busbar terminals, 76.2 mm wide
At 76.2 mm wide, 130 mm tall, and 70 mm deep, the 3VA1112-1AA32-0JA0 occupies the same 3-pole MCCB footprint as the rest of the 3VA1 160 A frame. The main current circuit connects via front busbar terminals — no lug terminals on this variant — so it is designed for busbar-stab mounting in a distribution panel or switchboard.