Siemens 6EP1931-2DC21 SITOP DC UPS Module 24V/6A DIN Rail No Interface

The Siemens 6EP1931-2DC21 is a SITOP DC UPS module that buffers a 24 V DC bus at 6 A, drawing 24 V/6.85 A on the input side to power the load and charge an external battery module at the same time. It has no communication interface, mounts on a 50 mm-wide DIN rail, and switches to battery backup at an adjustable 22-25.5 V threshold with a 1 s startup delay when the incoming supply drops.

Technical Specifications

Certifications & Standards

• CE
• EAC
• Shipbuilding
• ABS
• DNV
• EPD

Selection Notes

Without a communication interface, the 6EP1931-2DC21 handles buffering autonomously through its floating relay contacts (Bat/OK and Alarm/Bat) rather than reporting status over a serial link, so it suits installations where the 24 V OK / battery-in-use signal only needs to drive an indicator lamp or a digital input on a separate I/O module. The buffer threshold is adjustable from 22 to 25.5 V in 0.5 V steps, letting the switchover point be set above the normal supply's minimum tolerance so the module engages before a marginal PLC power dip. At 6 A output it draws 6.85 A on the input to power the load and charge the battery at the same time, so the upstream 24 V supply needs headroom beyond the 6 A load current.