AFDD-MCB combination, 20 A, C-curve, 1P+N
The Siemens 5SV6016-7KK20 is a compact AFDD-MCB combination from the SENTRON series, integrating arc-fault detection with overcurrent protection in a single 1 MW modular-width unit for 230 V AC residential and commercial final circuits. Rated 20 A with a C-curve tripping characteristic, it protects against both overload and short-circuit conditions up to 6 kA per EN 60898-1 and IEC 60947-2 — the standard breaking capacity for most domestic distribution boards. The 1P+N pole configuration switches the line conductor while the neutral is switched internally, suiting single-phase circuits where neutral isolation is required for the AFDD function.
Arc-fault detection range and selectivity
The AFDD detects series arcs between 2 A and 20 A and parallel arcs between 50 A and 500 A — the lower threshold catches glowing connections at the back of a junction box that a standard MCB would never trip on. Because the unit combines AFDD and MCB in one housing, there is no separate arc-fault sensor to mount in the panel — the entire protection chain lives in 18 mm of DIN-rail space.
Mechanical and environmental ratings
Rated for ambient temperatures from -40 °C to 75 °C, with a 55 °C limit at 95% relative humidity — covers unconditioned enclosures in both cold storage and plant-floor environments. The housing is halogen-free and silicon-free, meeting the material restrictions common in rail, marine, and clean-room installations where outgassing can damage nearby contacts or optics. IP20 protection applies with conductors connected; the device is rated for overvoltage category III and pollution degree 2, the standard specification for fixed-installation distribution boards.
Mounting and panel integration
Snaps onto DIN rail (REG) and occupies 1 modular width unit (18 mm) with a 70 mm installation depth — fits standard consumer units and sub-distribution boards without extra space. Mounting position is unrestricted, and the supply connection can be made from either end — useful when retrofitting into an existing board where the busbar orientation is fixed. The 68.5 mm depth leaves clearance behind most standard enclosure covers; verify the cover depth if the board uses a shallow trim plate.
Lifecycle and sourcing position
No stock-holding claim is made here. The mechanical service life is rated at 10,000 switching cycles typical — sufficient for branch-circuit protection in residential and light commercial panels where the device operates infrequently.