The Siemens 5SU1356-0KV06 is a combined residual-current and miniature circuit breaker (RCBO) — an FI/LS protector in Siemens' 5SU1 line. It packs a Type AC residual-current device with 30 mA sensitivity and a 6 kA breaking-capacity B-curve 6 A overcurrent trip into a single 1+N-pole module. The 70 mm depth fits standard distribution boards where space behind the DIN rail is tight.
What the ratings mean for fit
The 30 mA IΔn is the standard threshold for personal protection against direct contact in residential and commercial final circuits — it will trip on leakage currents that pass through a human body to ground. Type AC detection means it responds to sinusoidal AC fault currents only; pulsed DC or smooth DC faults (from rectified loads, variable-speed drives, or LED drivers) may not be detected, so this unit is suited for conventional resistive and inductive loads without power electronics. The 6 kA rated short-circuit capacity (Icn) means the device can safely interrupt a fault up to 6 kA at the declared voltage. In a domestic or light commercial installation with a typical upstream fuse or MCB rated at 6 kA or less, this coordinates without requiring a current-limiting backup. The B-curve (3–5 In magnetic trip) is the standard choice for resistive and general-purpose loads — lighting, socket outlets, small appliances — where inrush is modest. The 1+N-pole construction switches both phase and neutral, but the neutral pole is a switching neutral only — it does not provide overcurrent protection on the neutral conductor. The 6 A rated current (In) limits the protected circuit to a 6 A continuous load, typical for a lighting sub-circuit or a single socket outlet.