SENTRON 3VA2 — 500 A MCCB for Motor Protection
The Siemens 3VA2450-5MN32-0HC0 is a SENTRON-series molded case circuit breaker (MCCB) designed specifically for motor protection, rated 500 A continuous at 40 °C through 50 °C ambient. It carries a 3-pole configuration with an integrated shunt trip (STL) and two auxiliary switches (HQ) factory-fitted, so it arrives ready for remote trip and status feedback without additional wiring modules. Breaking capacity is 121 kA at 415 V and 440 V, dropping to 75.6 kA at 500 V and 9 kA at 690 V — figures that suit it for high-fault industrial distribution downstream of a transformer or upstream of motor control centers. The 187 kA rating at 240 V confirms it handles the worst-case bolted fault on a 240 V delta secondary.
Thermal Derating and Continuous Current
The breaker holds 500 A from 40 °C to 50 °C without derating. Above that, it steps down: 495 A at 55 °C, 490 A at 60 °C, 485 A at 65 °C, and 480 A at 70 °C. For a panel that runs warm — say a 55 °C internal ambient — you lose 5 A of headroom, not enough to force a frame-size jump, but worth confirming against the motor FLA plus service factor. Maximum power loss is 99 W at rated load. That heat stays inside the enclosure; factor it into the panel's thermal budget if the MCCB shares a compartment with solid-state drives or PLCs.
Dimensions and Panel Fit
Footprint is 138 mm wide by 248 mm tall by 110 mm deep (5.43 × 9.76 × 4.33 in).
Integrated Auxiliaries and Releases
Factory-installed shunt trip (STL) allows remote tripping from a PLC or E-stop circuit. Two auxiliary switches (HQ) provide normally-open and normally-closed contacts for status feedback — one pair for the breaker's open/closed state, the other for trip indication. No separate auxiliary switch block to order and snap on. Phase failure detection is built into the motor-protection curve. Undervoltage release is not fitted on this variant; if UVR is required, the 3VA2450-5MN32-0AA0 basic switch is the starting point for adding one.