What this MCCB is and what it does
The Siemens 3VA1125-6ED36-0AA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a 25 A continuous rating at 40 °C ambient, holds that rating through 50 °C, then derates to 23 A at 70 °C — so the thermal curve stays flat across typical panel ambient, and you only lose headroom above 55 °C. The TM210 overcurrent release combines a thermal bimetal for overload protection and a magnetic coil for short-circuit response; no undervoltage release or communication module on this variant, so it's a straight thermal-magnetic breaker for fixed-trip applications.
Interrupting capacity and voltage ratings
Interrupting capacity is 220 kA at 240 V, 154 kA at 415 V, 121 kA at 440 V, and 17 kA at both 500 V and 690 V. That 220 kA figure at 240 V covers high-fault utility feeds; the drop to 17 kA above 500 V means you verify the available fault current at the point of installation. Rated insulation voltage is 800 V, so the breaker's internal clearance and creepage are sized for 690 V systems with margin.
Panel fit and mounting
Three-pole, 76.2 mm wide, 130 mm tall, 70 mm deep — that's a standard 3-inch wide footprint for a 3-pole MCCB in this class. IP40 on the front means it's protected against tools and solid objects larger than 1 mm, but not sealed against moisture; keep it inside a panel enclosure. Max power loss is 8.5 W, so thermal rise inside a crowded enclosure is manageable — no forced cooling needed for the breaker itself.