What this MCCB delivers — and where the ratings matter
The Siemens 3VA1110-6FF42-0AA0 is a 4-pole SENTRON molded case circuit breaker rated for 100 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. The 220 kA breaking capacity at 240 V is the headline number for fault-clearing in high-available-fault-current panels — think main service entrance or large distribution board where the transformer is close. The same breaker delivers 154 kA at 415 V and 121 kA at 440 V, so it holds up across common global low-voltage networks. At 500 V and 690 V the rating drops to 17 kA, which still covers most motor-control-center fault levels but needs a coordination study if the upstream transformer exceeds that.
Thermal derating — the real-world current you can actually run
The 100 A rating holds flat from 40 °C through 50 °C, which is the typical panel ambient. At 55 °C it derates to 98 A, at 60 °C to 96 A, at 65 °C to 94 A, and at 70 °C to 91 A. If your enclosure runs hot — say a packed MCC in a non-conditioned room — the 91 A ceiling at 70 °C is the number to size against, not the nameplate 100 A. The TM240 release is a fixed thermal-magnetic design, no electronic adjustment, so the trip curve is set at the factory.
Panel fit and mechanical integration
The breaker measures 101.6 mm wide by 130 mm tall by 70 mm deep — a standard 4-pole MCCB footprint that drops into SENTRON mounting plates and most common panel cutouts. IP40 on the front means it is protected against tools and wires >1 mm, but not against water ingress; keep it inside a rated enclosure. The 20 000 mechanical endurance cycles cover routine switching for isolation or maintenance, not daily load-break duty.
Electrical ratings and compliance context
Rated insulation voltage is 800 V, and the maximum DC operational voltage is 600 V, so it can serve DC distribution in solar or battery storage applications within those limits. Maximum power loss is 25 W at rated current — factor that into enclosure thermal calculations. The N-conductor protection is designed at 50 %, meaning the neutral pole is rated for half the phase current, which is standard for 4-pole breakers in TN or TT systems where the neutral carries only unbalanced load.