The SITOP DC UPS 6EP1931-2EC42 is the USB-equipped 15A variant in Siemens' DC UPS family. It secures 360W of 24VDC load power against mains failures while providing a modern USB 2.0 interface for PC-based monitoring, trending, and remote control — a practical combination for automation panels that need both mid-range backup current and desktop visibility.

Power and Protection

The module accepts 22-29VDC input and delivers a regulated 24VDC output at up to 15A continuous, with 15.7A peak capability. Normal-mode efficiency of 96.2% minimizes cabinet heat and energy cost. The charging current — selectable at 0.35A or 0.7A via DIP switch — determines how quickly connected battery modules recharge after a discharge event. Short-circuit protection uses dynamic current limiting with automatic 20-second restart cycles.

USB Interface and Software

A USB 2.0 Full-Speed connection (Type B on the module, Type A on the PC) transmits status data every 75ms — BUFRD, ALARM, *BAT*, BA>85, BA<85 — plus voltage, current, and battery condition parameters. A one-time driver installation (available from siemens.com/sitop) enables the free SITOP DC UPS Software for graphical monitoring, event logging, and remote timer-start. Maximum cable length is 5m.

Key Decision Parameters

For RS-232 serial connectivity at the same power level, see the 6EP1931-2EC31 variant. External battery modules are ordered separately.