Reliable power for a sustainable world
Power Range: 10 - 40 kVA
3:3 1-3:1

Our third generation of transformerless ON LINE UPS systems, the 10-40 kVA Sentryum rewrites the concept of flexible power by offering a choice of three compact cabinet sizes to suit the needs of any small data centre or mission-critical application.  

Enhanced overload and short circuit capacity guarantee maximum availability. Incorporating a 5-inch colour touchscreen display and intuitive LED status indicator that automatically changes colour based on the UPS’s current operating state.  

Sentryum Range
Sentryum display


  • Flexible choice of 3 cabinet sizes (Compact, Active, Xtend) 

  • Operating efficiency up to 96.6% (ON LINE mode) 

  • Delivers unity power factor (kVA = kW) 

  • High overload and short circuit capacity 

  • Large colour touchscreen display and LED status indicator 

Brochures and data sheets

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10-40 kVA

Technical specifications of the model

The Sentryum (S3T) range is Riello UPS’s third generation of transformerless online uninterruptible power supplies.  

Available in 10-15-20-30-40 kVA versions, the Sentryum improves on our popular Multi Sentry (MST) series and has been developed following extensive customer feedback.

The S3T redefines the concept of flexible power protection by offering three different cabinet sizes to meet the varied needs of small data centres and mission-critical applications: 

Compact (CPT) 

  • Footprint less than 0.25 m2 and volume of 0.17 m3;  
  • 280 mm x 840 mm x 700 mm (W x D x H);
  • 1 internal battery string;
  • Specifically designed for extremely restricted spaces. 

Active (ACT) 

  • Footprint less than 0.35 m2 and volume of 0.33 m3
  • 380 mm x 850 mm x 1025 mm (W x D x H)  ;
  • 1 or 2 internal battery strings.

Xtend (XTD) 

  • Footprint less than 0.4 m2 and volume of 0.5 m3;  
  • 440 mm x 840 mm x 1320 mm (W x D x H);
  • Up to 3 internal battery strings in a single cabinet; 
  • Option to add isolation transformer;
  • Can upgrade enclosure protection from IP20 or IP21 to IP31. 

The Sentryum is manufactured used state-of-the-art components designed to run flawlessly at temperatures up to 40 °C. These include a dual-core DSP processor and three-level inverters that operate at high frequency (18 kHz). 

This ensures the S3T delivers full-rated power (kVA = kW 1 pf) with an exceptional operating efficiency of up to 96.6% in online double conversion mode.  

Available as three-phase/single phase input, single-phase output or three-phase input and output, the UPS has a unique control system that reduces harmonic voltage distortion (< 1% at resistive linear load and < 1.5% at non-linear load). 

In addition, the Sentryum has high overload (125% for 10 minutes, 150% for 1 minute) and short circuit (270% for 200ms and 150% for 300ms) capacity, which enables it to handle sudden peak loads without needing to transfer to bypass. 

Install up to 8 S3T together in parallel to scale capacity or build in redundancy (i.e. N+1 configuration). Closed loop system ensures the UPS continue to function even if there’s a disruption to the connecting cables.  

A revamped 5-inch colour touchscreen display panel clearly highlights crucial UPS measurements and operating statuses. While an innovative new LED status indicator automatically changes its colour (light blue, dark blue, yellow, red) depending on the operating mode and condition of the UPS. 

Full range of user-controllable operating modes including: 

  • ECO (up to 99% efficiency) 
  • Emergency (STANDBY OFF) 
  • Frequency Converter 

The Sentryum range is suitable for use with sealed lead-acid (VRLA), AGM, GEL, open vented or nickel cadmium batteries, as well as alternative backup sources such as supercapacitors and lithium-ion batteries. 

It incorporates sophisticated battery management systems, such as deep discharge protection and recharge voltage compensation, to ensure the best performance and operating life. Higher-powered (20 A) battery chargers are available for longer runtime applications.  

The S3T incorporates USB, RS232, and RJ10 ports, plus various slots to insert parallel and network communications cards. It is compatible with the full range of Riello UPS networking and UPS management software, including PowerShield3 and PowerNetGuard.