The Siemens 6EP4438-7FB00-3DX0 is a SITOP PSU8200 series power supply delivering a controlled 24 V DC output at 20 A from a 20.4–30 V DC input, with 98% efficiency. It snaps onto a DIN rail per EN 60715 35x7.5/15, occupying 45 mm width — a standard single-module slot in most control panels. The output voltage tracks the input minus roughly 0.2 V, so it's a buffer/booster unit rather than an isolated AC-DC converter; think of it as a regulated distribution module for an existing 24 V bus that needs extra current headroom or per-channel protection. Eight push-in outputs (0.5–4 mm²) each have individual electronic overload protection with a defined trip curve: 1.0× set value trips after about 5 s, 1.5× after 1 s, 1.8× after 0.1 s, and 2.0× after roughly 30 ms. Below 20 V input, an immediate switch-off triggers in about 8 ms if output exceeds the set point. A DIP switch selects between 25 ms, 200 ms, 500 ms, or load-optimized staggered startup for the outputs — useful when charging capacitive loads or sequencing field devices to avoid a single large inrush.
The enclosure measures 45 mm wide × 135 mm high × 125 mm deep, with a mounting height of 225 mm when snapped onto the DIN rail. IP20 rated, so it's intended for inside a cabinet — no washdown or outdoor exposure. The push-in terminals on the input side accept up to 16 mm² for the main 24 V feeds, while outputs and signaling contacts take up to 4 mm² and 1.5 mm² respectively. A remote reset input (non-isolated, >15 V signal level) lets a PLC or safety relay cycle the outputs after a fault without a manual panel visit.
The 98% efficiency means minimal heat dissipation — at full 20 A load, only about 10 W is lost as heat, so it can sit tight against other DIN-rail modules without derating for ambient temperature up to 70 °C (with natural convection). The controlled DC output with electronic overload per channel eliminates the need for individual branch fuses or circuit breakers on each load circuit, saving DIN rail space and wiring time. The 16 A internal fuse per output is not accessible — it's there as a last-resort protection against a hard short, not a serviceable component.