The Siemens 5SL6203-7CC is a SENTRON 5SL miniature circuit breaker — 2-pole, C-curve, rated 3 A at 400 V AC, with a 6 kA breaking capacity certified to EN 60898. The 2-pole version (2P) switches both phase and neutral, though it does not switch the neutral independently — note the 'no neutral conductor switching' flag in the design.
Overvoltage category 3 means it's designed for fixed-installation distribution boards, not for plug-in equipment. The 2-module width (36 mm) is the standard 2-pole footprint for DIN-rail enclosures; the 70 mm installation depth plus 76 mm overall depth fits common TP and N-series consumer units. Wire range accepts 0.75 to 25 mm² solid or stranded, with a recommended tightening torque of 2.5 to 3 N·m on the screw terminals. That covers everything from 1.5 mm² lighting circuits up to 6 mm² or 10 mm² submains.
Storage temperature range of -40 to +75 °C covers most warehouse and shipping conditions; ambient operating range is -25 to +45 °C, with periodic excursions to 55 °C at 95% humidity.