The Siemens 3RK1105-1BG04-0CA0 is an ASIsafe Basis Safety Monitor with two enabling circuits, designed to supervise safety functions on AS-Interface networks. It integrates into a control cabinet on a standard DIN rail, fastened by screws or snap-on mounting. The monitor type 2, version 3 supports safety applications up to Category 4 per EN 954-1, PL e per EN ISO 13849-1, and SIL 3 per IEC 61508.
The safety monitor provides two enabling circuits (safe outputs) and two release circuits. The enabling circuits are rated for AC-12 at 250 V, 3 A, and DC-12 (DC-1) at 24 V, 3 A — these are the maximum switching currents for resistive loads. The 24 V control supply draws 1 A; the 115 V and 230 V control supply options draw 0.1 A and 0.05 A respectively.
The monitor measures 45 mm wide, 108 mm high, and 120 mm deep — it occupies three modular width units on a DIN rail. The removable terminal blocks allow pre-wiring of the panel before inserting the monitor. AS-Interface protocol is supported natively, so the monitor communicates safety data over the same yellow cable as the standard AS-i slaves.