What this MCCB does and where it fits
The Siemens SENTRON 3VA1163-4EF36-0KA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection — meaning it sits at the feeder or main distribution point in a panel, not on a motor starter. It carries a rated continuous current Iu of 63 A and holds that rating flat from 40 °C through 50 °C; above that it derates to 60.48 A at 55 °C, 59.22 A at 60 °C, 57.96 A at 65 °C, and 56.7 A at 70 °C. The TM240 overcurrent release handles the thermal-magnetic trip curve, so it responds to sustained overloads and short-circuit events without an external relay. Breaking capacity is the headline number for an MCCB: this one delivers 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V. Those figures mean it can safely interrupt a fault current up to those levels without welding contacts or venting plasma — critical for high-fault panels near large transformers. The rated insulation voltage Ui is 800 V, so it's comfortable on 480 V and 600 V class systems. The breaker includes a shunt trip (STL) release for remote tripping — useful for emergency-stop circuits or downstream interlocking. It does not carry undervoltage release, auxiliary contacts, ground-fault monitoring, phase-failure detection, or communication functions. The integrated auxiliary trip is order code 3VA9688-0BL33 if you need to add remote indication later. Front protection is IP40, meaning it's splash-resistant from the front but not sealed for washdown environments.
What the ratings mean for your coordination study
The 63 A continuous rating with flat thermal performance up to 50 °C means this breaker won't nuisance-trip on a warm panel floor. The 121 kA interrupting rating at 240 V gives headroom for high-fault installations — typical utility transformer secondaries can deliver 65-100 kA at 240 V, so this breaker sits comfortably above that. At 480 V (415 V class), the 75.6 kA rating still covers most industrial service-entrance faults. The TM240 release is a fixed thermal-magnetic curve — no interchangeable trip units, so the trip settings are factory-set. If you need adjustable long-time or short-time pickup, look at the electronic-trip variants in the 3VA family.