What this MCCB is and where it fits
The Siemens 3VA2140-5MN32-0KC0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) built specifically for motor protection — the design-of-product field calls it out directly (cite:). That means the internal trip curve and thermal-magnetic response are tuned for motor inrush and overload profiles, not just general distribution. It's a 3-pole, 40 A frame with phase failure detection built in (cite:), so if you lose a phase upstream, this breaker will see it and trip — a key feature for preventing single-phasing damage on a motor load. Rated a full 40 A continuously across the entire operating temperature range from -25 °C to 70 °C (cite:–, –). No derating curve to chase at elevated panel temps — it holds its rating at 70 °C ambient. That's unusual; most breakers start stepping down above 40 °C. For a panel builder or site engineer, this simplifies the thermal budget in a crowded enclosure.
Breaking capacity — what the numbers mean for selectivity
This MCCB carries a massive 187 kA interrupting rating at 240 V (cite:), dropping to 121 kA at 415 V and 440 V (cite:–), then 75.6 kA at 500 V (cite:). At 690 V it's still rated 3.7 kA (cite:). Those are the maximum fault currents it can safely clear without welding or rupturing. For a commissioning engineer working on a 480 V panel, the 75.6 kA figure is the one that matters for SCCR compliance — that's well above what most industrial distribution transformers can deliver, so you've got headroom for coordination with upstream breakers. The short-time delay range is 4 to 17 seconds (cite:–), which gives you selectivity bandwidth downstream. If a feeder breaker needs to hold through a motor start (typically 6–10 seconds of locked-rotor current), you can set this to ride through without nuisance tripping on the main.
Built-in accessories — no add-on modules needed
Factory-fitted with a shunt trip release (STL) (cite:) and two HQ auxiliary switches (cite:). The shunt trip lets you remotely trip the breaker from a PLC or E-stop circuit — common for emergency-off chains or remote shutdown. The two auxiliary switches provide status feedback (open/closed) to a control system or indicator lamp. No separate accessory kit to order and install; it's all integrated at the factory. Dimensions: 105 mm wide, 181 mm tall, 86 mm deep (cite:,). That's a standard 3-pole MCCB footprint for a 40 A frame — fits existing SENTRON panel cutouts and busbar spacing. Mounts on a DIN rail or direct panel-mount via the rear slots.