Motor protection MCCB with ETU350M — what the ratings mean for fit
The Siemens 3VA2163-5MN36-0AH0 is a 3-pole SENTRON molded case circuit breaker (MCCB) built for motor protection, carrying 63 A rated continuous current (Iu) at 40 °C with no derating needed at that ambient — it holds 63 A through 50 °C, then steps down to 60.48 A at 55 °C and 56.7 A at 70 °C, so factor in panel heat rise if the enclosure runs hot. The ETU350M electronic trip unit handles phase-failure detection and adjustable overload curves, which is what you want for a motor branch circuit — thermal-magnetic breakers won't give you that granularity on the long-time pickup. Interrupting capacity is the headline here: 187 kA at 240 V, 121 kA at 415/440 V, 75.6 kA at 500 V, and 17 kA at 690 V. That's a lot of fault-current headroom — it means this breaker can sit upstream of a high-available-fault panel without needing a current-limiting fuse ahead of it, as long as the system voltage matches the rating. Auxiliary contact configuration ships as 2 auxiliary switches plus 1 trip alarm switch (HQ version), which is enough to signal the PLC both the breaker position and a trip event separately — handy for remote monitoring without adding a separate contact block.
Panel fit and integration
Dimensions are 105 mm wide, 181 mm high, 86 mm deep — a standard MCCB footprint for 63 A frame size. Front protection is IP40, so it's fine inside a closed panel but not rated for washdown or outdoor exposure without an enclosure. Rated insulation voltage is 800 V. Maximum power loss is 75 W. Operating temperature range is -25 °C to +70 °C, storage from -40 °C to +80 °C — fine for most industrial environments short of a freezer or oven line.