Transformer-protection breaker with 100 kA SCCR headroom
The Siemens 3RV2811-0GD10 is a SIRIUS S00 circuit breaker designed specifically for transformer protection, complying with UL 489 and CSA C22.2 No.5. Its 100 kA short-circuit current rating holds across the full voltage range — 240 V, 400 V, 500 V, and 690 V AC — so you don't need to derate the interrupting capacity when the transformer feeds a higher-voltage secondary. That SCCR headroom simplifies coordination downstream: the breaker can clear a bolted fault without cascading upstream, which matters when the panel feeds a critical process line. The S00 frame (97 mm deep, 45 mm wide, 144 mm tall) mounts via screw fixing or snaps onto a standard 35 mm DIN rail per DIN EN 60715. Terminal screws accept 1 to 10 mm² solid or stranded, up to 2×10 mm², with a Pozidriv #2 driver. That footprint fits a standard 45 mm-wide DIN slot — no panel mods needed to swap in from a similar S00 frame.
Clearance and mounting
Mounting position is any orientation. That 70 mm vertical gap is the one to watch in a crowded panel — if you're stacking breakers, leave at least that much breathing room for heat dissipation and arc-fault venting.
Environmental and auxiliary specs
The breaker has no ground-fault or phase-failure detection built in — those functions are handled externally if needed. Main contact screw terminals take an M4 screw. Mechanical endurance of the main contacts is rated at 100,000 typical cycles, and the maximum switching frequency under AC-3 duty is 15 operations per hour.