AEG Power Solutions Announces Protect Plus S500, Its New 3-phase Transformer-less UPS


  • On-line 3-phase UPS offering superior power protection to critical applications from 250 to 600kVA
  • Smart and flexible battery management, compatible with VRLA and Lithium batteries


AEG Power Solutions, a global provider of power supply systems and solutions for all types of critical and demanding applications, today announced the extension of its monolithic 3-phase UPS range with the launch of Protect Plus S500, its new transformer-less UPS that combines high AC/AC efficiency values with compact footprint, flexible battery management and low operating costs.


The system power range spans from 250 to 600kVA and up to 8 units can be connected in parallel, offering a wide scalability. Protect Plus S500 operates at up to 40°C without derating and can tolerate up to 50 °C environmental temperature. Its overload permanent capacity reaches up to 125% through the static bypass line.


Thanks to its full IGBT double-conversion technology Protect Plus S500 delivers first class load protection while minimizing installation and running costs. It combines low input THDi with almost unity input power factor and can operate in Eco Mode and Smart Eco Mode with an efficiency then reaching up to 99%, which reduces the energy costs. Production of waste heat is also significantly reduced, minimizing the air conditioning costs. This results in significant cost savings and contributes to reducing the carbon footprint of the installation.


With Protect Plus S500, AEG Power Solutions further introduces a new Smart Eco Mode. In this mode the bypass line is supplying the load while the inverter is synchronized with the bypass. The bypass line is continuously monitored. If poor power quality is detected at the AC line, the inverter will operate as harmonic compensation and power factor correction, while the bypass line stays connected to the load. This achieves a power efficiency of 98% at nominal load.


Protect Plus S500 offers advanced battery compatibility and flexible battery management. The system can operate with both standard VRLA or Li-ion batteries, and the battery string configuration is flexible (i.e. settable from 32 to 44 VRLA 12V battery blocks), adapting easily to any type of specific requirements. When 2 UPS are operating in parallel, a common battery string is also configurable.


To simplify and accelerate commissioning the UPS features an Intelligent Test Mode: the system uses its own nominal current (that flows in loop) to carry a self-test at full load, without using external dummy loads and saving energy.


Thanks to the 7’’ touch screen display and the wide range of connectivity options (SNMP, Modbus, programmable dry contacts, and USB for Service), the UPS can communicate its status in many ways.


Protect Plus S500 is easy to install and operate. It achieves high efficiency performance and its high-power density saves valuable floorspace for operations. Cost-effective and flexible, benefiting of advanced battery compatibility and management, the system is the solution of choice for a wide range of medium and large applications where power consumption, footprint and easy operation are at stake (transportation, manufacturing, building facilities or water infrastructures).


About AEG Power Solutions

AEG Power Solutions ensures continuous power availability and the safe operation of critical applications thanks to with a wide portfolio of power supply systems and services: AC and DC UPS, battery chargers, rectifier systems, service and maintenance on 24/7 basis, as well as fully customized UPS systems to customer specifications.
AEG Power Solutions has developed a distinctive expertise and world-class engineering capacities that bridge both AC and DC power technologies and span conventional and renewable energy platforms. AEG Power Solutions has decades of experience with UPS and power electronics, and grid integration, and is leveraging its conversion expertise to engineer and deliver solutions for the energy transition.


AEG Power Solutions is the sole subsidiary of the holding company 3W Power.

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