In a 24 V control system, even a brief power dip can cause a PLC to reboot, lose process data, and force a restart that takes hours. The 6EP1931‑2EC21 bridges those dips by switching to an external battery in microseconds, holding the 24 V DC rail stable until mains power returns or a controlled shutdown finishes. With 15 A capability and no built‑in communication, it is a straightforward, hard‑wired buffer that slots onto a DIN rail and works with SITOP BAT‑series batteries.

Backup Without Communication

• This module is the “no‑interface” variant — it handles the power switching autonomously and signals status through dry relay contacts and LED indicators. No software configuration, no network dependency.
• Ideal for remote pump stations, traffic systems, and machine tools where a simple, reliable backup is needed and a communication‑enabled UPS would add unnecessary complexity.

External Battery Required

• Connect any compatible SITOP BAT 24 V battery module. The internal charger delivers up to 2 A to recharge the battery once mains power is restored.
• Buffer time depends on the battery capacity and the actual load current. For a typical 10 Ah battery at full 15 A load, expect around 40 minutes of backup; at 5 A, well over 90 minutes.
• Efficiency stays above 95 % in buffering mode, so very little energy is lost as heat inside the panel.

Technical Specifications