What this MCCB is and what it does
The Siemens SENTRON 3VA1032-4ED32-0CA0 is a 3-pole molded case circuit breaker (MCCB) rated for 32 A continuous current, built for line protection in distribution panels and motor branch circuits. Its TM210 thermal-magnetic release handles overload and short-circuit protection without electronic adjustment — set it, torque it, and it runs. The 800 V rated insulation voltage (Ui) suits it for 400 V and 690 V industrial networks, and the 15 000-cycle mechanical endurance means it holds up in panels that see regular switching. Breaking capacity is the headline: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and still 11.9 kA at 690 V. That 75.6 kA at 415 V tells you this breaker handles high-fault scenarios common in European 400 V industrial mains without needing an upstream current-limiting fuse — it clears the fault itself.
Thermal derating — where the 32 A holds and where it doesn't
The 32 A rating is continuous at ambient up to 50 °C. Above that, the thermal-magnetic release starts to pull back: 30.72 A at 55 °C, 30.08 A at 60 °C, 29.44 A at 65 °C, and 28.8 A at 70 °C. If the panel runs hot — say, a sealed enclosure in a steel mill or a crowded switchboard — the effective ampacity drops. For a 32 A continuous load at 65 °C ambient, you'd need to step up to a 35 A frame or ventilate the enclosure. The derating curve is built into the TM210; no field adjustment.
Undervoltage release and integration
This variant ships with an undervoltage release (UVR) fitted — the auxiliary release design is the undervoltage type. When line voltage drops below the dropout threshold, the UVR trips the breaker open. That's useful for safety circuits, emergency-stop chains, or any scheme where a loss of control voltage must kill the load. The UVR's own order code is 3VA9608-0BB24, which is the spare part if the release fails. No auxiliary contacts are included (auxiliary contact version: without), so if you need status feedback to a PLC, you'll add a separate auxiliary switch block. Mounting is the standard SENTRON 3VA footprint: 70 mm deep, 76.2 mm wide (3-pole), 130 mm tall. Panel cutout and screw-terminal layout match the rest of the 3VA line, so swapping between 32 A and 63 A frames in the same enclosure position is straightforward. IP40 on the front face keeps dust out of the mechanism; the rear terminals are exposed, as is normal for panel-mount MCCBs.