The 6AG1961-3BA21-4AX0 is the SIPLUS version of the SITOP PSE202U redundancy module – same MOSFET decoupling technology, but with conformal coating that lets it breathe in chemically aggressive or humid atmospheres where a standard module would corrode. It takes two independent 24 V power supplies (each up to 20 A), decouples them with less than 0.5 V drop, and presents a single 40 A bus to your automation load. If one supply fails, the other carries the full load without interruption – and the built‑in relay tells your PLC about it.

How It Works

• Two SITOP 24 V supplies connect to the module's inputs.
• Active MOSFET decoupling replaces traditional diodes – voltage drop ~0.5 V vs. ~1.3 V for Schottky.
• Output is the sum of both input currents, up to 40 A total.
• Relay changeover contact (8 A/240 V AC) closes when both input voltages exceed the adjustable threshold (20–25 V).

Where It Matters

Use it wherever 24 V control power must survive a single power supply failure – process skids, emergency shutdown systems, burner management, wastewater treatment. The SIPLUS coating adds chemical resistance to cooling lubricants, salt spray, and biologically active substances per EN 60721‑3‑3.

Technical Specifications