What this part is and what it does
The Siemens 5SL5263-7CC is a 2-pole DC miniature circuit breaker from the SENTRON 5SL series, rated for a maximum of 72 V DC with a C tripping characteristic. The C-curve means it trips at 5–10 times rated current, so it handles moderate inrush from small DC motors, solenoids, or capacitive loads without nuisance trips. Breaking capacity is 10 kA per the DC rating — enough for most DC distribution panels in residential or light infrastructure.
Where it goes and how it mounts
Snaps onto a standard DIN rail. The 36 mm width takes up 2 modular width units, so it fits in a standard 18 mm/module panel grid. Depth is 76 mm, installation depth 70 mm — the extra 6 mm is the front projection of the toggle and sealable cover. Mounting position is any, so vertical or horizontal rail orientation works. IP20 with connected conductors means it's protected against solid objects larger than 12 mm but not against water — suitable for enclosed distribution boards, not outdoor or washdown locations.
What the ratings mean for fit
The 72 V DC maximum is the highest voltage this breaker can safely interrupt in a DC circuit. If your DC bus is 48 V or 60 V, this breaker covers it. The C-curve (5–10x In) avoids tripping on the startup surge of a small DC motor or a bank of capacitors — a B-curve would nuisance-trip on the same load. The 10 kA interrupting rating means it can clear a fault current up to 10,000 A without welding contacts or venting arc gas. For DC circuits, that's a solid margin for most panelboard faults.
Environmental and compliance notes
Rated for ambient temperatures from -40 °C to 75 °C, so it works in unconditioned enclosures or outdoor cabinets. Halogen-free and silicon-free construction — important for clean rooms or environments where outgassing could contaminate optics or electronics. Overvoltage category III and pollution degree 2 mean it's rated for fixed installation in building distribution panels, not for outdoor or wet locations. The sealable cover (yes) lets a panel builder or inspector lock the toggle position after commissioning.