What it is and what it does
The Siemens 5SU1324-6FP13 is a SENTRON RCBO — a combined residual-current circuit breaker with overcurrent protection — in a 2-pole, Type A, 30 mA, 13 A, B-curve configuration. It's the kind of device you'd find on a DIN rail in a distribution board, protecting a final subcircuit against both earth faults and overloads or short circuits. The Type A residual current detection means it catches pulsating DC fault currents on top of standard AC sine-wave faults, so it's suited for circuits with electronics like rectifiers or variable-speed drives. The B-curve trips between 3 and 5 times rated current, which is the standard for general-purpose resistive and small inductive loads in residential or light commercial panels.
Breaking capacity and thermal derating
This RCBO carries a 10 kA rated short-circuit capacity per EN 60898 and a 15 kA rating per IEC 60947-2. That 15 kA figure is the one that matters for industrial panel design: it tells you the device can safely interrupt a fault up to that level without welding its contacts or failing catastrophically. The thermal derating is honest and published: at 30 °C ambient it carries the full 13 A; at 40 °C it's 12.2 A; at 50 °C it's 11.2 A; at 60 °C it's 10.3 A. If your panel runs hot — say, a packed enclosure near a motor drive — you need to account for this, not just the nameplate 13 A.
Panel fit and mounting
The 5SU1324-6FP13 snaps onto a DIN rail and occupies 2 modular width units — that's 36 mm of panel width. Its depth is 72 mm, with 70 mm of installation depth needed behind the panel face. The supply can come from either top or bottom, and the mounting position is any orientation, which gives some flexibility when routing wires in a crowded enclosure. Touch protection is built in, and the IP20 rating holds once the distribution board is closed and conductors are connected.