The Siemens SENTRON 5SU1646-7FP10 is a 4-pole RCBO (residual current circuit breaker with overcurrent protection) in a 4-module-wide housing, rated 10 A at 30 °C with a C-curve tripping characteristic. It breaks fault currents up to 6 kA per both EN 60898 and IEC 60947-2, making it suitable for final-circuit protection in residential and commercial distribution boards where both overcurrent and earth-fault protection are required in a single device.
What the ratings mean for fit
The C-curve (tripping between 5 and 10 times In) is the standard choice for general-purpose circuits feeding socket outlets, lighting, and small appliances where moderate inrush currents occur — it avoids nuisance tripping from motor-start or capacitive loads that a B-curve would catch. The 10 A rating at 30 °C derates to 9.6 A at 40 °C, 9.1 A at 50 °C, and 8.2 A at 70 °C; if the distribution board runs warm, size the upstream protective device accordingly. The 6 kA breaking capacity (Icn) per EN 60898 and IEC 60947-2 is adequate for most residential and light-commercial installations where the prospective short-circuit current at the board is below that threshold. Overvoltage category III and pollution degree 3 ratings confirm it is designed for fixed installation within a distribution board, not for outdoor or washdown environments — IP20 applies only when the board is installed and conductors are connected. Supply can enter from either the top or bottom, which simplifies busbar alignment and panel wiring. The 4-pole design with all poles protected (4P) means it switches and protects all four conductors — three phases plus neutral — in a single module, saving DIN-rail space compared to separate MCB and RCCB units.
Panel integration notes
The 72 mm wide module occupies 4 standard modular-width units on a DIN rail. Depth is 72 mm, installation depth 70 mm — verify enclosure depth clearance before committing, especially in shallow consumer units. The 85 mm height fits standard distribution board cutouts. Mounting position is any orientation, which helps in tight enclosures where vertical or horizontal rail layouts are used. The supply can enter from top or bottom, so busbar routing is flexible. The IP20 rating is conditional on the board being installed with conductors connected — the RCBO itself is not sealed against dust ingress when exposed.