What it is and what it does
The Siemens 3VA1110-4FF46-0AA0 is a SENTRON molded case circuit breaker (MCCB) for line protection. Four poles, rated 100 A continuous (Iu) at 45 °C, with a TM240 thermal-magnetic overcurrent release. The TM designation means the thermal element handles overloads (adjustable long-time pickup), and the magnetic element handles short-circuits (fixed instantaneous trip). The 240 suffix indicates the magnetic trip threshold is set at 240 A — 2.4× the 100 A frame rating, which keeps it from nuisance-tripping on motor inrush or transformer energization.
Breaking capacity — what the voltages mean
Breaking capacity varies sharply with system voltage: 121 kA at 240 VAC, 75.6 kA at 415 VAC, 52.5 kA at 440 VAC, and 11.9 kA at both 500 VAC and 690 VAC. On a 480 V panel (common in North America), the 52.5 kA at 440 V is the nearest published figure — expect the actual rating at 480 V to fall between that and the 11.9 kA at 500 V. For a 400 V IEC distribution board, the 75.6 kA figure covers most high-fault scenarios. The 800 V rated insulation voltage (Ui) confirms the breaker is built for 690 V line-to-line systems.
Thermal derating — don't size by the nameplate alone
The 100 A rating holds at 45 °C and 50 °C. Above that, it derates: 98 A at 55 °C, 96 A at 60 °C, 94 A at 65 °C, and 91 A at 70 °C. If the panel ambient hits 60 °C, the breaker's effective continuous current is 96 A — not 100. The maximum operating temperature is 70 °C, and the storage range is -40 °C to 80 °C. Power dissipation at rated load is 25 W maximum, which matters for enclosure thermal calculations.
Fit and panel integration
Dimensions: 130 mm high, 101.6 mm wide, 70 mm deep. IP40 on the front.
Lifecycle and sourcing reality
Current production — no end-of-life notice. The 3VA platform is Siemens' active MCCB generation.