What this MCCB is and where it fits
The Siemens SENTRON 3VA1110-4EF32-0DC0 is a 3-pole molded case circuit breaker (MCCB) rated for 100 A continuous current, built around a TM240 thermal-magnetic overcurrent release. It's the line-protection variant in the 3VA series — meaning it's tuned for feeder and distribution duty rather than motor-circuit protection, so the trip curve is set for cable and busbar protection. Breaking capacity is the headline number that decides whether this breaker clears a fault or welds shut. At 240 V it's rated 121 kA; at 415 V it's 75.6 kA; at 440 V it drops to 52.5 kA; at 690 V it's still 11.9 kA. That's a high-interrupting-capacity (HIC) class — it sits upstream in a distribution board, not downstream at a final subcircuit. If your fault-current study shows anything above 65 kA at 415 V, this is the breaker that keeps selectivity alive without cascading upstream.
Thermal derating — the real-world current limit
The 100 A rating holds flat from 40 °C through 50 °C. At 55 °C it's 96 A; at 60 °C it's 94 A; at 65 °C it's 92 A; at 70 °C it's 90 A. That's a gentle slope — about 2 % per 5 °C above 50 °C — so in a warm panel you don't lose much headroom. The rated insulation voltage is 800 V, which covers 690 V line-to-line systems with margin.
Built-in auxiliaries and releases
This breaker ships with 2 auxiliary switches (HQ type) fitted — that's two form-C contacts for status feedback to a PLC or annunciator panel. It also includes an undervoltage release (UVR), which trips the breaker when control voltage drops below a threshold. That's a common requirement for emergency-stop chains and safety circuits where loss of control power must open the main breaker. The UVR is the integrated-trip design, order code 3VA9608-0BB25 if you need a spare or replacement module.
Panel fit and environmental limits
Dimensions are 70 mm deep, 76.2 mm wide, 130 mm tall — a standard 3-pole MCCB footprint that drops into SENTRON distribution boards and most third-party enclosures with a 76.2 mm (3-inch) mounting centre. Front-face protection is IP40, so it's fine in a clean indoor panel but not for washdown environments. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.