SENTRON 3VA1 MCCB for motor and feeder protection
The Siemens SENTRON 3VA1163-5MH32-0JA0 is a 3-pole molded case circuit breaker rated 63 A at 40 °C, designed for starter protection in motor branch circuits and distribution feeders. Its TM120M thermal-magnetic release provides overload and short-circuit protection with a fixed thermal element and magnetic trip calibrated for motor inrush. The integrated shunt trip (STL) allows remote tripping via a control signal — useful for emergency-stop or safety circuits that need to drop the breaker without a manual handle operation. Interrupting capacity is the headline here: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 7.5 kA at both 500 V and 690 V. Those numbers mean this breaker can be applied on high-fault panels downstream of large transformers without cascading — the 187 kA at 240 V covers virtually any US low-voltage fault level, while the 7.5 kA at 690 V still exceeds typical industrial motor-start SCCR requirements. The rated insulation voltage of 800 V confirms it is built for 690 V systems with headroom. Thermal derating is published per degree: holds 63 A flat from 40 °C through 50 °C, then drops to 62 A at 55 °C, 61 A at 60 °C, 60 A at 65 °C, and 58 A at 70 °C. In a sealed panel running hot, expect to downrate the continuous load by about 8 % at 70 °C. Maximum power loss is 17.3 W — relevant for thermal calculations in compact enclosures.
Mounting and integration
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits Siemens SENTRON distribution blocks and panel-mounting plates. The 70 mm depth leaves room behind the panel for wiring without forcing a deeper enclosure. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. No trip indicator on the front face — status is read from the handle position or via the shunt trip signal.