Siemens SENTRON 3VA1110-3EF42-0AA0 — 100 A MCCB for Line Protection
The Siemens 3VA1110-3EF42-0AA0 is a 4-pole molded case circuit breaker from the SENTRON 3VA series, rated 100 A at 40 °C and designed for line protection in distribution panels. It carries a TM240 thermal-magnetic overcurrent release, meaning the thermal element is fixed at 100 A and the magnetic trip is adjustable up to 240 A — the setting range you'd dial in to coordinate with downstream branch breakers. Breaking capacity is 75.6 kA at 240 V, 52.5 kA at 415 V, and 32 kA at 440 V, so it handles high-fault-current scenarios on 480Y/277 V or 400 V industrial services without cascading upstream. The 800 V rated insulation voltage confirms it's built for 690 V systems as well.
Current Rating and Thermal Derating
The breaker holds 100 A continuously at ambient temperatures up to 50 °C. Above that, it derates linearly: 98 A at 55 °C, 96 A at 60 °C, 94 A at 65 °C, and 91 A at 70 °C. If your panel runs hot — say, near a drive cabinet or in a non-conditioned enclosure — use the 55 °C figure as your de facto rating to avoid nuisance tripping.
Physical Fit and Panel Integration
The breaker measures 130 mm high, 101.6 mm wide, and 70 mm deep — a 4-pole footprint that fits standard SENTRON 3VA mounting bases. The front face carries an IP40 protection rating, so it's suitable for enclosed distribution boards where tools or fingers won't contact live parts. No undervoltage release or communication module is fitted on this variant, so it's a straight thermal-magnetic unit with no auxiliary wiring.
Selectivity and Coordination Notes
For selectivity studies, the TM240 release gives a fixed thermal pickup at 100 A and a magnetic trip adjustable from 5× to 12× In (500–1200 A). The 75.6 kA interrupting rating at 240 V provides headroom for transformer-fed services. Maximum power loss is 25 W — factor that into enclosure thermal calculations if the breaker is tightly grouped.