What this MCCB is and what it does
The Siemens SENTRON 3VA1196-4EF32-0BH0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection — the primary job of interrupting fault currents in distribution panels and protecting downstream cables and equipment. It carries a rated continuous current Iu of 16 A and a rated insulation voltage Ui of 800 V, so it fits into 400 V and 690 V line-to-line systems without exceeding the insulation base. Breaking capacity is the headline number that decides whether this breaker clears a fault without welding or rupturing: 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V. That 121 kA figure at 240 V means it handles very high available fault current on the secondary side of a step-down transformer — common in large commercial or industrial switchboards. The 11.9 kA at 690 V still covers most 690 V motor control center bus faults.
Thermal-magnetic release and temperature derating
The overcurrent release is a TM240 — a fixed thermal-magnetic type set for 16 A at 40 °C ambient. The breaker holds 16 A from 40 °C up to 50 °C, then begins to derate: 15.36 A at 55 °C, 15.04 A at 60 °C, 14.72 A at 65 °C, and 14.4 A at 70 °C. If the panel ambient runs above 50 °C, the actual continuous current the breaker can carry without nuisance tripping is lower than the 16 A nameplate; plan the load accordingly. The magnetic trip is fixed inside the TM240 release — no field-adjustable magnetic setting. For applications needing adjustable short-circuit pickup, a different release variant (e.g., an electronic ETU) would be the correct choice. This part is a straight thermal-magnetic, line-protection MCCB.
Auxiliary contacts and undervoltage release
This MCCB ships with an integrated auxiliary contact block: 2 auxiliary switches plus 1 trip alarm switch (HQ configuration). That gives remote status of the breaker position (ON/OFF) and a separate alarm contact that closes only when the breaker trips on fault — useful for PLC inputs, annunciator panels, or safety circuits that need a dedicated trip signal. An undervoltage release (UVR) is fitted as standard. The UVR trips the breaker when the control voltage drops below a set threshold — required in many European machine-safety schemes to ensure the breaker opens on loss of control power. The specific auxiliary trip module order code for this build is 3VA9608-0BB11, which is the UVR module itself.
Physical fit and panel integration
Footprint: width 76.2 mm, height 130 mm, depth 70 mm. That 76.2 mm width is a standard 3-pole MCCB pitch — it fits a 3-module-wide cutout on a DIN-rail mounting plate or a direct-panel mount. Depth of 70 mm leaves room behind the door for wiring space; the front face carries a trip indicator (red flag visible when tripped) and an IP40 protection rating on the front, meaning tools or fingers cannot reach live parts from the front, but the sides and rear are not sealed against dust ingress. The breaker is designed for fixed mounting (not plug-in) and accepts copper or aluminum cable lugs. The TM240 release is non-interchangeable in the field — if you need a different rating, you replace the whole MCCB, not just the trip unit.