New Industry Products

3-Phase Input, 1250W Military Field-Grade Hot-Swappable UPS

January 24, 2020 by Paul Shepard

SynQor, Inc., announced its new 3-phase balanced input military field-grade uninterruptible power supply. In addition to providing a glitch-free continuous power to loads, this UPS also tackles the difficult problem of unbalanced loads on 3-phase systems in aircraft and ships.

MIL-STD-1399-300B requires that all the phase currents be balanced to within ±5% for ships and ±3% for submarines. Achieving this high degree of phase current balance with today’s single-phase electronic loads is now easy with the new SynQor 3-phase input UPS.

The 3-phase input UPS allows single-phase loads to appear at the power source as a clean, well behaved, nearly zero reactance balanced MIL-STD-1399-300B compliant 3-phase load. The 3-phase input UPS has a floating ground option for air or sea craft applications that might require that feature.

This 3-phase input UPS is compact, ultra-light, fully isolated and designed for military and aerospace applications. This military field-grade UPS is designed to withstand the harshest and extreme electrical, shock/vibration and environmental conditions. The UPS can draw power from a 3-phase “Wye” or “Delta” connected ac source or from a 28Vdc power source, if equipped with the optional dc input port.

The backup power of the system is provided by an advanced highly efficient, low weight, compact, sealed lithium polymer battery pack. SynQor’s battery packs can significantly outperform other market solutions in the same class. The single-phase output of the 3-phase UPS can be selected to be 115- or 230-Vrms at 50-, 60- or 400-Hz with a maximum output capacity of 1250W/1500VA.

The 3-phase input UPS also has two optional ports, DC1 and DC2. The DC1 port can deliver several different voltages from 12- to 50-Vdc at 500W. The DC2 port, if the UPS is not equipped with the dc input option, can deliver up to 1250W of regulated or semi-regulated 24-, 28- or 50-Vdc.

Additional options for the UPS system include:

  • a SNMP/Ethernet base module that allows real time remote system monitoring with trap/email features that warn users and monitoring consoles of important system events;
  • a 2U enclosure that increases battery run time from 10 to 24min;
  • a feature that allows wide dynamic input frequency range of operation (47- to 800-Hz) for variable frequency input ac applications; and,
  • a droop share option that allows for load sharing of the DC2 output and a redundant (N+M) option that allows multiple UPS units to load share in either single-phase, split-phase or 3-phase configurations.


  • Balanced load currents for 3-phase sources; MIL-STD-1399-300B
  • Universal ac input: 80- to 265-Vac; 47- to 65-Hz or 47- to 800-Hz
  • Output Power: 1250W/1500VA at 115- or 230-Vrms at 50-, 60- or 400-Hz
  • Built-in Load Sharing and Redundant (N+M) capabilities
  • >10min. or >24min. battery run-time at full power
  • 1U High Rack-Mount unit (17" x 22.53" x 1.73")
  • Low Weight: 32 lbs.

Specification Compliance

  • MIL-STD-1399-300B
  • MIL-STD-810G
  • MIL-STD-461F
  • MIL-STD-704F
  • MIL-STD-1275D