What it is and what the ratings mean for fit
The Siemens SENTRON 3VA1096-4ED32-0BA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying 16 A continuously at up to 50 °C and derating to 15 A at 65–70 °C — so the thermal trip curve is set for a 16 A load, but the breaker stays in its rated band even in a warm enclosure. The 121 kA breaking capacity at 240 VAC is the headline number, but the real-world fit depends on the available fault current at your service voltage: 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. That means this breaker can sit on a 690 V line with an 11.9 kA SCCR, which covers most motor-control-center applications but not high-fault industrial mains at that voltage. The overcurrent release is a TM210 — thermal-magnetic, fixed at 16 A, with a magnetic trip threshold of 10× In (160 A). That is a standard motor-starting curve: it holds through inrush on a 10–12 A full-load motor but clears a hard short fast. The 800 V rated insulation voltage (Ui) gives headroom for 690 V systems without derating the dielectric.
Undervoltage release and panel integration
This variant ships with an undervoltage release (UVR) built in — the auxiliary release type is explicitly an undervoltage release (UVR). That means the breaker trips automatically if the control voltage drops below a set threshold, which is standard for safety circuits where a loss of control power must drop the load (e.g., emergency-stop chains or machine-guarding interlocks). The UVR is wired separately from the main power path; verify the coil voltage rating against your control supply before panel wiring. The 3VA frame is a compact 76.2 mm wide, 130 mm tall, and 70 mm deep — three modules wide on a standard DIN rail or panel-mount footprint. At 13.1 W maximum power loss, it sheds heat into the enclosure; in a sealed cabinet above 50 °C, account for the 15 A derating. No communication module, no ground-fault monitoring, and no trip indicator on this variant — it is a straight thermal-magnetic breaker with UVR, sized for a clean line-protection role.