Panel-builder commissioning notes
The C12F34V160B is a Schneider Electric ComPacT NSXm 3-pole moulded-case circuit breaker (MCCB) rated 160 A at 40 °C with a MicroLogic 4.1 electronic trip unit. Built to EN/IEC 60947-2, this is a Category A utilisation device — meaning it is not specifically intended for motor-starting duty but for distribution applications where the breaker sees low-frequency switching. The electronic trip unit includes a 20-minute thermal memory that retains heat history before and after tripping, preventing reclosure onto an overloaded circuit that hasn't cooled. The 9-module pitch (144 mm height, 108 mm width, 80 mm depth) fits standard distribution panel cutouts.
Earth-leakage integration and selectivity
Unlike a standard MCCB that requires a separate earth-leakage module, the C12F34V160B integrates earth-leakage protection directly into the MicroLogic 4.1 trip unit. Sensitivity settings cover 30 mA, 100 mA, 300 mA, 500 mA, 1 A, 3 A, and 5 A for both class A (pulsating DC) and class AC (sinusoidal AC) residual currents. This simplifies panel wiring and reduces enclosure space compared to a breaker-plus-module combination. For selectivity coordination downstream, the 20-minute thermal memory helps maintain time-current discrimination when a temporary overload trips the breaker and is reset before the thermal replica has fully reset. The electronic trip unit also supports zone-selective interlocking (ZSI) when paired with compatible upstream breakers, though this requires additional wiring between trip units.
IP40 front-face protection (IK07 impact resistance) suits the breaker for installation in enclosed distribution boards where tools or debris might strike the toggle. Operating altitude is 2000 m without derating, extending to 5000 m with derating applied. Ambient relative humidity range is 0–95 %, non-condensing. Mechanical durability is rated at 20,000 cycles; electrical durability at 20,000 cycles at rated current at 440 V, halving to 10,000 cycles at In/2. The grey (RAL 7016) toggle and housing are standard for the ComPacT NSXm range. A green flag on the front signals presence of auxiliary contacts, aiding quick visual checks during commissioning without opening the panel door.
