The Siemens 5SU1356-1DV32 is a combined residual current device and miniature circuit breaker (RCBO) — an FI/LS-protector — in a single 1+N-pole module. It provides both earth leakage and overcurrent protection for a final subcircuit, rated at 32 A with a 30 mA residual operating current and a 6 kA short-circuit breaking capacity. The Type AC designation means it detects sinusoidal AC residual currents only, which covers the majority of residential and commercial loads without electronic components.
What the ratings mean for fit
The 30 mA sensitivity is the standard for personal protection against direct contact in IEC 60364 installations — it clears a fault before the let-through energy reaches a dangerous level. The 6 kA breaking capacity (Icn) is suitable for domestic and light commercial distribution boards where the prospective short-circuit current at the point of installation does not exceed that value. The C-curve (32 A) provides a magnetic trip threshold of 5–10× In, designed for loads with moderate inrush such as lighting banks or small motor circuits. The 1+N-pole configuration switches the line conductor and disconnects the neutral, which is the common arrangement in single-phase TN or TT systems.
Deployment context
The 70 mm depth (D=70MM) and pig-tail neutral connection are designed for flush mounting in standard consumer units and distribution boards where space behind the DIN rail is limited. The 1+N-pole width occupies a single modular slot, preserving panel density.