The Siemens 3RV1915-5B is a SIRIUS 3-phase supply terminal designed to feed power from below into the 3-phase busbar system for S00 and S0 frame-size circuit breakers. This is the part that brings line power onto the busbar stack — not a breaker itself, but the feed-in point that powers the entire row of S00/S0 motor-protective or branch circuit devices above it.
The terminal measures 44 mm wide, 73 mm high, and 48 mm deep — a compact footprint that fits within the standard S00/S0 busbar stack height. It connects from below the busbar, which matters for panel layout: the feed-in cable enters from the bottom, leaving the top of the busbar free for the plug-in breaker modules. Screw terminals accept solid 1x (2.5…16 mm²), stranded 1x (2.5…25 mm²), or wire with ferrule 1x (4…16 mm²). AWG equivalents for the main circuit are 1x (12…4). Insulation voltage is rated 690 V AC at pollution degree 3.