Motor protection MCCB with ETU550M — 500 A frame
The Siemens 3VA2450-5MP32-0AA0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) in the motor protection variant, carrying a continuous rated current Iu of 500 A at 40 °C ambient. It is a 3-pole device fitted with the ETU550M electronic overcurrent release, which provides adjustable trip classes 10A, 10/10E, 20/20E, and 30 — matching the thermal overload curve to the motor's starting profile. The breaker includes phase failure detection and a communication function, making it suitable for integration into monitored motor control centers.
Breaking capacity across the voltage range
The interrupting rating is voltage-dependent: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V. At 415 V, that 121 kA figure provides substantial fault-current headroom for most industrial distribution panels — the breaker will clear a bolted fault without cascading upstream. The 9 kA at 690 V is the low end of the curve; if your system runs at 690 V and available fault current exceeds that, you need a current-limiting upstream device or a higher-rated frame.
Thermal derating and ambient limits
Rated current holds at 500 A from 40 °C through 50 °C ambient. Above that, derating is linear: 477 A at 55 °C, 455 A at 60 °C, 432 A at 65 °C, and 410 A at 70 °C. If the panel ambient runs at 55 °C, the breaker's continuous capability drops by 23 A — that matters when sizing for a motor that draws 480 A continuously. Operating ambient range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
Dimensions and panel fit
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep. The 110 mm depth is the dimension from the mounting surface to the front of the breaker — important when the enclosure depth is tight, especially with door-mounted rotary handles or auxiliary modules added. Width of 138 mm is the standard 3-pole frame footprint for the 3VA2 500 A platform; it occupies three 45 mm-wide pole spaces on a DIN rail or bolted bus.