Riello Sentryum S3T 40 Online UPS 40kVA / 40kW – Three-Phase

The Riello Sentryum S3T 40 is a 40kVA / 40kW three-phase online double-conversion UPS from Riello UPS's third-generation transformerless Sentryum range. It delivers full rated power at unity power factor (kVA = kW) with efficiency of up to 96.5%, and a compact cabinet that suits small data centres, server rooms, network infrastructure, building systems, and other mission-critical loads. A 5-inch colour touchscreen, USB, RS232, and RJ10 ports, communication card slots, and parallel capability for up to 8 units make it easy to monitor, expand, and build redundancy.

ONLINE DOUBLE CONVERSION: CLEAN, REGULATED POWER ALL THE TIME

In online double-conversion mode the UPS rebuilds the output power continuously, so connected equipment always runs on clean, regulated power with no transfer time when the mains fails, drops, or surges. Servers, storage, network equipment, and industrial controls stay isolated from brownouts, spikes, and noise on the utility supply.

40KVA = 40KW: UNITY POWER FACTOR

The S3T 40 delivers its full 40kW of real power at unity power factor, so a 40kVA rating means 40kW of usable load. Many UPS systems at this size give up 10% or more of their rating to a lower power factor, so unity PF lets you size for the load you actually have.

TRANSFORMERLESS, THREE-PHASE (S3T)

The S3T version has three-phase input and three-phase output. The transformerless design is compact and light for its capacity, and Riello builds on its Multi Sentry (MST) series with an optimised card layout that reduces components, cables, and interconnections, which saves installation space and eases maintenance. Optional isolation transformers are available.

UP TO 96.5% EFFICIENCY

Efficiency reaches up to 96.5% in online double-conversion mode, with high efficiency maintained from loads as low as 50%. Less wasted energy means lower running cost and less heat to remove from the room.

LOW HARMONIC DISTORTION

The control system keeps output voltage harmonic distortion below 1% with resistive loads and below 1.5% with non-linear loads such as switch-mode server power supplies.

BUILT FOR REAL ENVIRONMENTS

Sentryum uses a dual-core DSP processor and high-frequency three-level inverters (18kHz), with components engineered to operate at temperatures up to 40°C. A closed-loop parallel arrangement keeps a parallel system running even if the connecting cables are severed. Enhanced overload and short-circuit capacity add resilience.

5" COLOUR TOUCHSCREEN + LED STATUS INDICATOR

A 5-inch colour touchscreen shows measurements and operating states clearly, and an LED indicator changes colour with the UPS's operating mode and status, so you can read the condition from across the room.

PARALLEL UP TO 8 UNITS

Connect up to 8 units in parallel to increase capacity or build N+1 redundancy as your load grows.

CONNECTIVITY AND MANAGEMENT

USB, RS232, and RJ10 ports and communication card slots support network and building-management integration. Compatible with Riello UPS management software including PowerShield3 and PowerNetGuard.

FLEXIBLE BATTERY OPTIONS

Smart Battery Management extends battery life. The range supports sealed lead-acid (VRLA) AGM, open-vent, GEL, and nickel-cadmium batteries, and some versions accept extended battery packs for longer autonomy.

BUILT FOR

- Server rooms and small data centres

- Network, telecom, and security infrastructure

- Industrial control and process equipment

- Medical and laboratory equipment

- Building-critical systems

KEY SPECIFICATIONS

- Model: Riello Sentryum S3T 40

- Type: Online double-conversion, transformerless, standalone

- Power: 40kVA / 40kW (unity power factor)

- Phases: Three-phase input / three-phase output (S3T), 400V

- Efficiency: up to 96.5%

- Output Voltage Distortion: < 1% resistive, < 1.5% non-linear

- Inverter: High-frequency three-level (18kHz), dual-core DSP

- Display: 5" colour touchscreen + LED status indicator

- Interfaces: USB, RS232, RJ10, communication card slots

- Parallel: up to 8 units

- Battery Types: VRLA AGM, open-vent, GEL, Ni-Cd

- Software: PowerShield3, PowerNetGuard

- Manufacturer: Riello UPS