Safety monitor for AS-Interface safety networks
The Siemens 3RK1105-1BG04-2CA0 is an ASIsafe extended safety monitor with expanded functionality, designed to supervise safety circuits on an AS-Interface network. It provides 2 enabling circuits (2 F-RO outputs) and achieves a maximum response time of 40 ms, making it suitable for guarding applications where fast reaction to a safety demand is required. Rated for use up to Category 4 per EN 954-1, Performance Level e per EN ISO 13849-1, and SIL 3 per IEC 61508, this monitor integrates into safety-rated control systems for machinery guarding, press lines, and automated assembly cells where a safety-rated stop is required within the AS-Interface loop.
The 24 V control supply draws 1 A — this is the current the monitor pulls from the AS-Interface power supply or an auxiliary 24 VDC source. For a field-service tech isolating a fault: if the 24 V rail is sagging, this monitor's draw is a known load to account for. The 115 V and 230 V ratings (0.1 A and 0.05 A respectively) are for the enabling circuit outputs — these are the contact ratings for switching loads at those voltages. The DC-12 (DC-1) 24 V rating of 3 A and the AC-12 250 V rating of 3 A define the maximum continuous current the safety outputs can carry under resistive loads. For a controls integrator: if your enabling circuit drives a contactor coil or a pilot light, stay within these limits. The 40 ms response time is the maximum delay from a safety input demand to the outputs opening — critical for stopping distance calculations in safeguarding applications.
IP20 rated, so it belongs in a clean, dry control cabinet — not on the machine frame in a washdown zone. I/O connections use spring-loaded terminals — no screwdriver needed for wiring, which speeds panel assembly and reduces loose-connection callbacks. The reference code per EN 61346-2 is F, meaning it's classified as a protective device in the system documentation.