What this MCCB delivers
The Siemens 3VA1120-5EF32-0AC0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in 3-pole configuration. Its 20 A continuous current (Iu) holds at ambient up to 50 °C without derating; above that the thermal curve drops to 19.2 A at 55 °C and 18 A at 70 °C — relevant if the panel runs hot near the top of a sealed enclosure. The TM240 overcurrent release is a fixed thermal-magnetic type — no adjustable trip curve, so it's a straight swap for a panel that already calls for a 20 A TM240 MCCB. Auxiliary contacts come as 2 HQ switches, which is enough to signal the breaker state back to a PLC or status lamp without an add-on module.
Breaking capacity — what the voltages mean
This MCCB delivers 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V. That 187 kA at 240 V is the headline number for North American 240/120 V split-phase or 240 V three-phase panels; the 121 kA at 415 V covers most European 400 V industrial grids. The 17 kA at 690 V is the limit for 690 V drives or mining gear — if your fault current at 690 V exceeds that, step up to a higher-rated frame.
Panel fit and integration
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures. The front face carries IP40 protection, so it's fine inside a closed cabinet but not for washdown zones. Operating temperature range is -25 °C to +70 °C; storage from -40 °C to +80 °C. No undervoltage release, no ground-fault monitoring, no communication function — this is a pure overcurrent breaker with auxiliary contacts only.