What this MCCB delivers and where it fits
The Siemens SENTRON 3VA2450-7MN32-0JL0 is a 3-pole molded case circuit breaker (MCCB) in the motor protection version, rated for 500 A continuous current at 40 °C through 50 °C with only a 5 A derating step at 55 °C. Its ETU350M electronic trip unit provides phase failure detection and a voltage trigger, making it suited for protecting motor feeders and other inductive loads in industrial switchboards and motor control centers. The 330 kA breaking capacity at 240 V gives substantial fault-current headroom for high-available-fault installations; at 415 V it still interrupts 242 kA, so it coordinates well downstream of larger air circuit breakers without requiring current-limiting fuses in most utility-grade distribution.
Breaking capacity and selectivity planning
At 690 V the 3VA2450-7MN32-0JL0 still clears 52.5 kA, which covers most 690 V industrial networks. The 800 V rated insulation voltage (Ui) confirms the internal creepage and clearance are designed for 690 V line-to-line systems. For a site electrical engineer building a selective coordination study, the 242 kA at 415 V means this MCCB can be the main or feeder breaker in a 400 V panel where the transformer secondary fault current is in that range, and its electronic trip unit allows adjustable I²t curves to achieve Type 2 coordination with downstream motor starters.
Panel integration and physical fit
The 3VA2450-7MN32-0JL0 measures 138 mm wide, 248 mm high, and 110 mm deep. It mounts into a standard Siemens SENTRON 3VA draw-out or fixed cradle; the 138 mm width is three pole spaces wide on a 45 mm per-pole pitch. The front IP40 protection means it is suitable for installation in enclosed switchboards where no water spray is present. The auxiliary contact configuration — 2 auxiliary switches plus 1 trip alarm and 1 electrical alarm switch (HQ) — provides remote status feedback without requiring a separate interface module.
Trip unit and auxiliary release details
The overcurrent release is an ETU350M electronic unit, which supports adjustable long-time, short-time, instantaneous, and ground-fault protection settings (ground-fault monitoring is not fitted on this variant). A shunt trip (STL) is integrated as the auxiliary release, allowing remote tripping from a PLC or emergency-stop circuit. The supplied basic switch is order code 3VA2450-7MN32-0AA0, and the integrated auxiliary trip is 3VA9688-0BL32 — useful for a panel OEM wireman ordering spare or replacement sub-assemblies. Maximum power loss is 99 W, which should be factored into enclosure thermal calculations.