PWM Series Single Phase Static Digital AC Voltage Stabilisers.

  • PWM SERIES microprocessor controlled Single Phase Static Digital Voltage Stabilisers automatically correct brownouts (by boosting low voltage) and over-voltages (by reducing high voltage). They are, designed to ensure the delivery of a stable and quality output voltage.
  • Being designed for many years of reliable service, VSi’s PWM models provide protection from incoming line voltage sags, spikes and surges / swells. As Static Digital solutions, they are virtually maintenance free and offer an exceptionally fast speed of correction, making them ideal for the most sensitive of electrical and electronic loads.

+ General Technical Specifications >

This Specification covers the general technical performance of the H Series (220-240V) Single Phase 2 Wire PWM Series Voltage Stabilisers in ratings from 2.1 to 14 kVA.

Design Topology: IGBT & MOSFET / Pulse Width Modulated (PWM) Inverter / Rectifier Solid State Design
Electrical Configuration: Single Phase 2 Wire (1 Phase + Neutral + G / E)
Power Ratings: 2.1 kVA (9.1 Amps), 3.5 kVA (15.2 Amps), 5.25 kVA (22.8 Amps), 7 kVA (30.4 Amps), 10.5 kVA (45.6 Amps) & 14 kVA (60.8 Amps)
Power Factor: The Power Factor has no effect on performance providing the stabiliser is being used within its rated capacity
Frequency 50 / 60 Hz
Voltage 230 V
Frequency 50 / 60 Hz
Permissible Input Voltage Window 230V ±25% (173V to 287V)
Voltage: 230V
Voltage Regulation: ±1%
Frequency 50 / 60 Hz
LCD Digital Metering: Input & Output Volts,
Input & Output Frequency
Output Current (Amps) & Load Level (%)
Internal Temperature (°C)
Status Indicators: Normal Operation Available
Stable Output Voltage
Overload of Fault - In Automatic Electronic Bypass Mode
Overload or the existence of an abnormal condition
Audible Alarms: Fault and Over Voltage
Communications: RS-232 Serial Port
Over Current: Input & Output Breakers - as Standard
Spike & Surge Protection: MOV (Metal Oxide Varistor)
Noise Protection: EMI Filters
Overload Protection: More than 105% Output Automatically Disconnected - requiring Manual Restart (Output Under Limit 188V ±4V, Over Limit 270V ±4V)
Over & Under Voltage Protection: Protects against high and low voltage with automatic output disconnection requiring manual restart
Short Circuit Protection: Automatic output disconnect requiring manual restart
Manual Maintenance Bypass - Inbuilt: Fitted as standard on 3.5 kVA Models and Above.
The ability to manually re-route the supply feed to bypass the stabilisation function
Operating Temperature Range: 0 to 40°C. Derate by 2% for each additional °C Up to max 60°C
Storage Temperature Range: -20 to 50°C
Maximum Altitude: 2000 Metres. Derate by 1% for each additional 100m
Relative Humidity: Suitable for indoor use up to 90% Relative Humidity (non-condensing)
Cooling: Forced fan cooling
Acoustic Noise Level: @1 Metre: <50 dbA
Construction: Sheet metal enclosure to IP20 / NEMA 1 Style - BS EN 60529 - with Plastic Molded Front Cover
Colour: RAL 7047 (Telegray 4)
Dimensions: - W x D x D (mm) 2.1 kVA - 258 x 333 x 422 | 3.5 kVA - 258 x 333 x 422 | 5.25 kVA - 258 x 333 x 422 | 7 kVA - 258 x 333 x 422 | 10.5 kVA - 258 x 546 x 531 | 14 kVA - 258 x 546 x 531
Packed: - W x D x D (mm) 2.1 kVA - 39 x 45 x 54 | 3.5 kVA - 39 x 45 x 54 | 5.25 kVA - 39 x 45 x 54 | 7 kVA - 39 x 45 54 | 10.5 kVA - 41 x 78 x 68 | 14 kVA - 41 x 78 x 68
Weight: (Packed) - W x D x D (mm) 2.1 kVA - 23 Kg (26 Kg) | 3.5 kVA - 29 Kg (32 Kg) | 5.25 kVA - 30 Kg (33 Kg) | 7 kVA - 32 Kg (35 Kg) | 10.5 kVA - 58 Kg (69 Kg) | 14 kVA - 62 Kg (73 Kg)
EMC Conformance: BS EN 55022 and relevant parts of BS EN 61000
CE Certification: Fully Compliant - 2014/30/EU (The EMC Directive) and 2014/35/EU (The Low Voltage Directive)
Standard Warranty: 24 Months / 2 Years from date of supply

+ Digital Display Panel & RS-485 Remote Communications >

Digital Display Panel

ESR-Display-Panel-HComprehensive Digital Monitoring and Control Panel delivering intuitive control and monitoring of all the key system parameters.

Input Voltage: (I/P Vac) Voltage level of the incoming utility mains supply
Output Voltage: (O/P Vac) Output voltage delivered by the system
Input Frequency: (I/P Hz) Frequency of the incoming utility mains supply
Output Frequency: (O/P Hz) Output Frequency delivered by the system
Load Currant: (O/P) Power (Amps) drawn by the connected load
Temperature: (°C) Internal Temperature of the system
Load Level (%) Bar Graph showing percentage load level

All Okay - in line mode
In Bypass Mode
Stable Output Voltage
Output Overload or an Abnormal Condition exists

Over Voltage

RS-232 Serial Port-Standard on ALL Models

+ Front & Rear Views - 2.1 to 7 kVA Models >


Front View


Rear View 

(2.1 kVA)


Rear View

(3.5 to 7 kVA)

+ Input & Output Connections >

Plug N Play (2.1 kVA Model)


Please Note: PWM Voltage Stabilisers are NOT FOR USE with life sustaining equipment, or any device where the power requirement exceed the “Maximum Power Ratings” listed in the General Technical Specification table.

These Stabilisers are not designed to support / protect voltage “back feed” applications, where energy is required to be also fed back into the utility supply.

Copyright © VSI (UK) reserves the right to change any or all of the specifications indicated or implied without prior notice. E&OE

+ Brochure / Data Sheet

To download / view the PDF Data Sheet simply click on the PDF icon below.



PWM SERIES 2.1 kVA to 14 kVA Single Phase Static Digital AC Voltage Stabilisers

+ Operator and User Manuals

To download / view the PDF User Manual simply click on the PDF icon below.



PWM SERIES 2.1 kVA to 14 kVA Single Phase Static Digital AC Voltage Stabilisers

+ CE Certification

PWM Series Single Phase AC Voltage Stabilisers comply with the relevant European Union (EU) health, safety and environmental protection directives and regulations and are duly CE marked.

Copyright © VSI (UK) reserves the right to change any or all of the specifications indicated or implied without prior notice. E&OE




PWM SERIES 2.1 kVA to 14 kVA Single Phase Static Digital AC Voltage Stabilisers

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