What it is and what it does
The Siemens 5SL6663-7CC is a SENTRON miniature circuit breaker rated 63 A with a C-curve tripping characteristic, in a 3P+N (4-pole) configuration. It is designed for 400 V AC systems and carries a 6 kA breaking capacity according to EN 60898 — the standard that governs overcurrent protection in residential and commercial final circuits. The C-curve means it trips between 5 and 10 times rated current, so it handles moderate inrush from motorized loads like pumps or compressors without nuisance tripping, while still clearing a hard fault.
Where it fits
This breaker occupies 4 modular width units (72 mm) on a DIN rail, with a depth of 76 mm and height of 90 mm. The installation depth behind the panel is 70 mm. It mounts in any position and is rated IP20 with connected conductors — standard for enclosed distribution boards. The housing is halogen-free and silicon-free, which matters for panels in clean-room or food-processing environments where outgassing can contaminate product or sensitive electronics.
What the ratings mean for the panel
The 6 kA breaking capacity at 400 V AC per EN 60898 is the standard rating for this class — it safely interrupts fault currents up to that level in a residential or light-commercial distribution board. The 3P+N configuration switches all three phases and switches the neutral, which is required for TN-S or TN-C-S systems where the neutral is not bonded to ground at the board. The C-curve is the most common choice for general-purpose circuits feeding socket outlets, lighting, and small motor loads. The breaker accepts supplementary devices (auxiliary contacts, shunt trips, alarm switches) for remote status or emergency-off functions.