800 A MCCB with ETU550 — selectivity and panel fit
The Siemens SENTRON 3VA2580-5JP32-0AB0 is a 3-pole molded case circuit breaker rated for 800 A continuous current, built around the ETU550 electronic trip unit. The 800 A rating holds flat across the 40 °C to 60 °C ambient range — no derate needed until 65 °C (767 A) and 70 °C (703 A), which simplifies panel layout in warm enclosures. Breaking capacity runs 187 kA at 240 V, 121 kA at 415 V, and 53 kA at 690 V — numbers that put this in the high-fault tier for industrial mains distribution. The ETU550 offers adjustable long-time (Ir 0.5–1.0 x In), short-time (tsd 0.05–0.5 s), and instantaneous pickup, plus ground-fault protection is not built in (specified as 'without'). Physical footprint is 210 mm wide, 320 mm tall, 120 mm deep — a standard SENTRON 3VA frame size that fits existing 3VA panel cutouts. Front IP40 protection is adequate for enclosed switchboards; no IP rating on the rear or sides, so internal segregation within the panel matters.
Panel integration notes
The 210 mm width and 120 mm depth match the standard 3VA frame drilling pattern — drop-in compatible with existing SENTRON mounting plates and busbar systems. No rewiring needed if replacing a same-frame 3VA breaker; verify the lug kit matches the cable/ busbar termination (the order code does not include a specific lug kit, so that's a separate line item). Power loss is rated at 135 W maximum — account for that in enclosure thermal calculations, especially if the panel is densely packed or operating near the 70 °C upper ambient limit.