What this RCCB is and where it goes
The Siemens 5SV3344-3KK60 is a 4-pole residual current circuit breaker (RCCB) from the SENTRON family, rated 40 A, 30 mA AC/DC sensitive, with an additional 6 mA DC detection path branded SIGRES. It is designed for electro-mobility (EV charging) circuits where Type F short-time delayed tripping handles the smooth DC ripple from modern onboard chargers and inverters — standard Type A RCCBs can nuisance-trip or fail to detect those waveforms. Snaps onto a DIN rail (REG) and occupies 4 modular width units (72 mm wide). Mounting position is any, so it fits tight enclosures. The 70 mm depth matches standard distribution board cutouts. Rated IP20 once the distribution board is installed and conductors are connected — this is a panel-mount device, not a standalone outdoor unit.
Key ratings and what they mean for your BOM
Rated 40 A at 400 V AC, 4-pole. The 6 mA DC detection (SIGRES) addresses smooth DC fault current from EV inverters. Short-circuit current rating is 10 kA per IEC 61008-1 (0.8 kA rated conditional). That means the device can safely interrupt a fault up to 10 kA at the rated voltage, provided the upstream protective device (MCB or fuse) is coordinated. The maximum permissible series fuse is 100 A — match that when designing the branch circuit. Operating frequency is 50/60 Hz, supply voltage range 70–440 V AC. Mechanical service life is 10,000 cycles.
Panel fit and integration notes
Four modular width units at 60 mm grid spacing means 72 mm of DIN rail. The 70 mm installation depth is standard for SENTRON RCCBs — verify the enclosure depth if retrofitting into a shallow panel. Power supply can enter from top or bottom; for the SIGRES function, supply from the top keeps detection active even when the RCCB is switched off. Supplementary devices (e.g., auxiliary switches, shunt trips) can be installed on the right side. The device is silicon-free, which matters for applications where silicone outgassing can contaminate contacts or optics.