Multi Sentry On-line Double Conversion AC UPS

Three Phase Uninterruptible Power Supply from 60kVA to 200kVA

MULTI SENTRY is a state-of-the-art uninterruptible power supply, achieving the highest possible level of on-line double-conversion performance (VFI-SS-111) as defined within IEC EN 62040-3. The UPS has been designed to protect critical information and telecommunications systems, networks, services and processes whose operation could be disrupted by poor power quality and/or breaks in their mains power supply.

The sizes available include:  60kVA – 80kVA – 100kVA – 125kVA – 160kVA – 200kVA all with a three-phase input and output.


MULTI SENTRY can be used for a wide range of applications, thanks to its configuration options, flexibility, accessories and performance levels:

  • Suitable for powering capacitive loads, for example Blade servers – without any reduction in active power, from 0.9 leading to 0.9 lagging
  • Modes of operation include: On-Line, Eco, Smart-Active and Stand-By/Off
  • Frequency conversion mode
  • Power Share connections for priority-based load shedding when the mains power supply has failed
  • Cold-start facility to switch the UPS on even without a mains power supply present
  • Extensive back-up time options using battery extension cabinets
  • Optional battery cabinet temperature sensor to assist the temperature compensating charger
  • Optional battery chargers to optimize recharge times
  • Optional dual input supplies
  • Optional isolation transformers for Galvanic isolation and neutral connectivity

Maximum Reliability and Availability

Distributed parallel configuration of up to 8 units per redundant (N+1) or power parallel system. The UPS continue to operate in parallel even if the connection cable is interrupted (Closed Loop).

Battery Care System

Proper battery care is critical to ensuring correct UPS operation in emergency conditions. The Riello UPS battery care system consists of a series of features and capabilities to optimise battery management and obtain the best performance and operating life possible.

Battery recharging: Multi Sentry is suitable for use with hermetically sealed lead acid (VRLA), AGM and GEL batteries and Open Vent and Nickel Cadmium batteries. Depending on the battery type, different charging methods are available:

  • One-level voltage recharge, typically used for widely available VRLA AGM batteries;
  • Two-level voltage recharge according to IU specification;
  • Charge blocking system to reduce electrolyte consumption and lengthen the life of VRLA batteries

Temperature compensation: to avoid excessive voltage being applied to the batteries in a high ambient

Battery test: to detect performance degradation and predict battery failure.

Deep discharge protection: to prevent the batteries being discharged below a level from which they cannot be recovered (especially when discharged over long periods with very low loads).

Low AC ripple current: from a high-frequency battery charger, to ensure the batteries are not subjected to this damaging element commonly experienced with some other UPS and power supply designs.Wide input voltage range: from a rectifier that can work down to less than 40% of its nominal supply rating (at half load), removing the need to discharge the batteries.

Low Management Cost

The MULTI SENTRY design provides exceptional performance and efficiency levels:

  • High efficiency up to 96% – saving up to 35% in dissipated energy in one year compared to a more traditional UPS (91%) resulting in a faster payback period of four years.
  • High output power factor which at 0.9pF (1pF for models 160-200 kVA) provides up to 15% ( 20% for models 160-200 kVA) more active power compared to a more traditionally sized UPS – providing greater system expansion margin for further load increases.


ModelRated  Power (kVA)Active Power (kW)Power Factor
MST 6060 540.9
MST 8080720.9
MST 100100900.9
MST 125125112,50.9
MST 1601601601
MST 2002002001


Frequency50/60 Hz
Frequency tolerance40 – 72 Hz
Power factor at full load> 0.99
Current distorsionthdi ≤ 3%
Nominal Voltage380-400-415 Vac three-phase + N
Number of phases3 + N
Voltage tolerance180 – 264 V (selectable)
Nominal Frequency50 or 60 Hz (selectable)
Frequency tolerance±5 (selectable)
Bypass Overload125% for 60 minutes, 150% for 10 minute
Power factor0.9
Number of phases3+N
FrequencyCan be selected: 50 Hz or 60 Hz or self-learning
Static variation± 1%
Dynamic variation± 3%
Current crest factor3 : 1 Ipeak/Irms
Frequency stability during battery
TypeVRLA AGM/GEL/NiCd/Li-ion/Supercaps
Typical recharge time6 hours
ColorDark grey RAL 7016
Communication 3 slots for communications interface / USB / RS232
Safety complianceIEC EN 62040-1; EMC IEC EN 62040-2 C2
EMC conformanceEMC 2004/108/CE electromagnetic compatibility Directive
Protection ratingIP20
Smart Active efficiencyup to 99%
Operating temperature0°C / +40°C
Relative humidity< 90% not condensed

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