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Uninterruptible power supplies (UPS) and standby generators

Hazard Knowledge

An uninterruptible power supply (UPS) is electrical equipment that provides emergency power when the input power source, typically the mains, fails. UPS can range from small units to large rooms containing batteries.

Uninterruptible power supplies provide immediate protection from input power interruptions; this is done by supplying energy stored in batteries, super capacitors or flywheels. 

The operating time of most uninterruptible power supply systems is relatively short, usually only a few minutes. This is sufficient to start a standby power source or to properly shut down and protect the equipment, such as:

  • Computers
  • Data centres
  • Telecommunication equipment
  • Other electrical equipment where an unexpected power disruption could cause injuries, fatalities or serious business disruption

Standby generators

Personnel attending incidents may need to manage electrical standby generators and associated fuel supplies.

In the event of the electricity supply to the facility being interrupted, the standby generator will automatically start to operate, resulting in the re-energising of power supplies.