The Siemens SENTRON 3VA2140-5MN32-0DC0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuously at 40 °C, with no derating needed up to 70 °C — the full 40 A holds across the entire ambient range. Breaking capacity at 415 V is 121 kA, which puts it in the high-interrupting class for industrial distribution: it can clear a bolted fault on a large transformer secondary without cascading upstream. The design is explicitly for motor protection, with phase failure detection built in, so it tracks the load current on all three phases and trips on an open phase before the motor single-phases to failure.
Auxiliary releases and switch configuration
Factory-fitted with an undervoltage release (UVR) and two HQ auxiliary switches. The UVR drops the breaker on loss of control voltage — standard for emergency-stop chains or undervoltage protection schemes where the load must not auto-restart after a dip. The two auxiliary switches provide status feedback (open/closed) to a PLC or indication lamp, with HQ designation meaning high-quantity switching cycles for frequent signaling. The base switch is order code 3VA21405MN320AA0, so the UVR and aux switches are integrated at the factory, not field-added.
Physical fit and panel integration
Dimensions are 105 mm wide, 181 mm high, 86 mm deep — a standard 3-pole MCCB footprint for DIN-rail or panel-mount installation. The 86 mm depth leaves clearance for rear-connected busbars or cable lugs in a typical 200 mm deep enclosure. Power loss at rated current is 4.1 W maximum, so thermal rise inside a sealed panel is manageable; no forced ventilation required for a single unit, but group multiple breakers and account for the cumulative dissipation.
Ambient and storage range
Operating ambient -25 °C to +70 °C covers most indoor industrial environments, including unheated warehouses and hot motor control centers. Storage range -40 °C to +80 °C — the breaker can sit in a cold warehouse or a shipping container without damage, as long as it's not energized outside its operating limits.