What this 800 A MCCB delivers
The Siemens 3VA2580-5JP32-0DH0 is a SENTRON molded case circuit breaker (MCCB) rated 800 A continuous at 40 °C through 60 °C, with a 3-pole configuration and an ETU550 electronic trip unit for line protection. It handles fault currents up to 187 kA at 240 V, 121 kA at 415 V, and 53 kA at 690 V — numbers that matter when you're coordinating downstream devices and need the SCCR headroom to avoid cascading failures. The trip unit gives you adjustable long-time (tr) from 0.5 to 25 s and short-time (tsd) from 0.05 to 0.5 s, so you can shape the curve to the load without swapping breaker frames.
The breaker measures 210 mm wide, 320 mm tall, and 120 mm deep — a standard panel-mount footprint for this class. Front IP40 protection means it's suited for enclosed switchboards where dust ingress is controlled but not washdown. The ETU550 communicates, so you can pull trip data and events over the bus without opening the door.
Thermal derating and endurance
Full 800 A rating holds through 60 °C ambient; at 65 °C it derates to 767 A, and at 70 °C to 703 A. That thermal headroom means you don't lose capacity in a warm enclosure unless it's genuinely hot. Mechanical endurance is 10,000 operations — a solid number for a main breaker that cycles infrequently but needs to be reliable when it does.