Critical Power Supplies Ltd


Whether you want an off-the-shelf, bespoke or turn-key solution, come and talk to Critical Power Supplies and benefit from over fifty years within the power protection and energy management fields. No other supplier can boast the depth of manufacturer knowledge available when it comes to standby power systems, generators, ups batteries, static transfer switches and uninterruptible power supplies.

Critical Power Supplies consists of two divisions focusing on the use of power and energy within critical installations. The company supplies individual systems and full turn-key packages with comprehensive 24-7 service and maintenance packages. The company is geared towards acting in the most environmentally friendly way and to providing its clients and stakeholders with an ECO approach to power and energy management.

The commercial arm of the business is based in Thame, Oxon from where the company supplies a wide range of off-the-shelf and built-to-order power and energy management systems. A nationwide service team provides round-the-clock maintenance to some of the UK’s most demanding clients across a broad spectrum of industries and disciplines.

UPS Manufacturers

Critical Power Supplies Ltd has pleasure in offering the following products and services.

Manufacturers product offered include:

  • APC by Schneider Electric. (Smart-UPS, Smart-UPS RT, Smart-UPS on-line, Symmetra, Powerchute). 
  • Eaton UPS including Powerware and MGE Solutions. (5110, 3105, 5125, 9130, 9135, 9140, Ellipse ASR, EX RT, MX, Evolution).
  • Gamatronic including modular and military solutions.
  • GE Digital UPS. (Match, Match L, GT, LP, LP 33, Vision,)
  • Riello UPS, (Dialog Vision, iDialog, iPlug, Master Dialog, Master Plus, Sentinel Dual, Sentinel Power, Sentinel Pro)


  • CSB Batteries
  • Yuasa Batteries

Renewable Energy Solutions:

  • SMA Inverters
  • Moser Baer Solar Panels
  • Victron Energy
  • Fuel Cells


  • Installation
  • Battery replacement
  • Recycling of legacy solutions
  • Remote monitoring
  • Servicing


UPS for PCs, POS Terminals and small File Servers

Uninterruptible power supplies up to 800VA to protect small applications requiring a ‘fit and forget’ UPS system with a small battery back-up and protection from mains borne spikes, electrical noise, sags and surges.

Network UPS

UPS for Networks, Servers and Telecom's, Switches and Critical Applications

These UPS solutions are ‘plug and play’ offering a built-in battery back-up runtime with options for additional extended runtime upto several hours. Formats include: tower UPS, floor standing UPS, rackmount UPS and dual format UPS capable of either tower or 19" rackmount installation.

Blade Server Room UPS

UPS for Blade Servers, Comms and Server Rooms.

Uninterruptible power supplies (UPS) 3-15kVA for larger critical applications including server and comms rooms running the latest Blade servers, virtual PABx and file servers.

Datacentre UPS

UPS for Datacentres and Telecoms Switching Centres

Uninterruptible power supplies from large power projects from 20-800kVA installed as part of a centralised or decentralised power protection plan.

Rackmount UPS

Rack mount: 500VA-10kVA

Rackmount Uninterruptible power supplies(UPS) up to 10kVA for installation in 19" rack cabinets from 1U high and less than 500Dmm in size.



Single Phase UPS

Single Phase Output UPS Systems / Standby Power

Single phase output Uninterruptible power supplies (UPS) / Standby Power with a single phase (1/1) or three phase (3/1) input supply. UPS Systems up to 3kVA use ‘fit and forget’ but may also be hardwired for additional power security.

Three Phase UPS Systems

Three Phase Output UPS Systems

Three phase output Uninterruptible power supplies (UPS) with a three phase (3/3) input supply. Available as high efficiency and on-line double conversion UPS

Industrial UPS

UPS for Industrial, Marine and Off-shore applications

Uninterruptible power supplies for special projects including industrial (ruggedised) and 110Vac, medical and marine, and Central Supply Systems (CSS) for use with emergency lighting and security applications.

Medical Grade UPS

The Medical Grade Uninterruptible Power Supplies UPS solutions from Critical Power Supplies to IEC60601-1 providing a high performance solution for the medical environment.

Source Transfer Switches (STS)

Source Transfer Switches (STS) or Static Transfer Switches is another name they have been called, are used to increase the resilience of power continuity plans by introducing a dual-input source of primary AC power.

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