63 A MCCB with 187 kA interrupting — what that means for your panel
The Siemens 3VA1163-5EF32-0AA0 is a SENTRON molded case circuit breaker rated 63 A continuous at 40 °C, with a TM240 thermal-magnetic trip unit. That 187 kA breaking capacity at 240 V is the headline number for fault-duty coordination — it safely clears a bolted fault up to that level without upstream cascading. The 3-pole, line-protection design means it's sized for feeder or main breaker duty, not motor-circuit protection with an overload relay. Frame dimensions are 130 mm high, 76.2 mm wide, 70 mm deep (-), so it fits standard 3-pole MCCB panel cutouts.
Thermal derating and ambient — the real continuous current
This breaker holds its full 63 A rating through 50 °C (-). At 55 °C it derates to 62 A, at 65 °C to 60 A, and at 70 °C to 58 A (-). That's a shallow derating curve — useful for panels with elevated internal ambient near other heat sources. The TM240 release is fixed thermal-magnetic; no electronic adjustment or communication function.
Breaking capacity across voltages — selectivity planning
Interrupting rating drops with system voltage: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V (-). For a 480 V panel, the 75.6 kA at 440 V is the relevant figure — that's the available fault current the breaker can interrupt. Insulation voltage is rated 800 V, so it's suitable for 690 V line-to-line systems. The front protection class is IP40, meaning tools and fingers are blocked but not water ingress — standard for enclosed panel mounting.
Panel fit and footprint
At 70 mm deep and 76.2 mm wide, this breaker occupies one standard 3-pole MCCB slot. No undervoltage release, no ground-fault monitoring, no voltage-trigger accessory — it's a bare thermal-magnetic line-protection device. The 17.3 W maximum power loss is moderate; account for it in enclosed panel thermal calculations, especially when grouping multiple breakers. Operating temperature range is -25 °C to 70 °C (-); storage range is -40 °C to 80 °C (-).