RCBO for final-circuit protection — 2-pole, C-curve, 20 A, 30 mA Type A
The Siemens 5SU1353-7KK20 is a 2-pole RCBO (residual current circuit breaker with overcurrent protection) from the SENTRON series, combining a C-curve miniature circuit breaker (20 A rated current) with a 30 mA Type A residual current device in a single 36 mm wide module — 2 modular width units on the DIN rail. The Type A residual current detection covers pulsating DC fault currents and sinusoidal AC — the standard requirement for circuits with single-phase electronics, switched-mode power supplies, or variable-speed drives downstream. At 30 °C ambient the device carries the full 20 A; derate linearly to 14.6 A at 70 °C per the published temperature table — a consideration when the RCBO is packed into a warm enclosure with other heat sources.
The 5SU1353-7KK20 carries a current production lifecycle status from Siemens.
Mounting and integration — DIN-rail final-circuit protection
Touch protection is provided on the terminals per the product feature listing.
The device is classified as energy limitation class 3, meaning it limits let-through energy to a level that protects downstream equipment under fault conditions.