Siemens 3VA1120-5EF32-0JC0 — SENTRON 3VA Molded Case Circuit Breaker, 20 A, 187 kA IC at 240 V
The Siemens 3VA1120-5EF32-0JC0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for line protection, with a rated continuous current Iu of 20 A and a TM240 thermal-magnetic overcurrent release. Its interrupting capacity reaches 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — figures that govern selectivity and SCCR coordination in a distribution panel.
Current derating and thermal limits
The breaker carries its full 20 A rating from 40 °C through 50 °C. Above that, derating applies linearly: 19.2 A at 55 °C, 18.8 A at 60 °C, 18.4 A at 65 °C, and 18 A at 70 °C. For panel builders, this means the 20 A frame can be used in a 50 °C ambient without downsizing the circuit; above that, the load current must be adjusted per the published curve.
Integrated accessories and auxiliary circuits
This variant includes a shunt trip (STL) for remote tripping and two HQ auxiliary switches for status feedback to a PLC or indication panel. The auxiliary release design is specified as 3VA9688-0BL32. The breaker does not include undervoltage release, phase failure detection, ground fault monitoring, or communication functions — it is a straightforward line-protection device with basic remote-trip and contact-signal capability.
Mechanical and environmental ratings
Dimensions: 130 mm height, 76.2 mm width, 70 mm depth — fits standard 3-pole MCCB panel cutouts. Front protection is IP40. Mechanical endurance is rated at 15,000 operations. Operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C.