What Is Involved In Installing Or Replacing A Standby Generator?

Installing a standby generator involves assessing the site's power requirements, selecting suitable equipment, and ensuring it can safely supply the necessary electrical loads during a mains power failure. The installation must be designed around the building's electrical infrastructure, operating requirements, and available space.

What is involved in installing a standby generator?

The process typically begins with a site survey and load assessment to establish the required generator capacity, identify which equipment needs backup power, and determine where the generator can be installed.

The electrical installation may include power cabling, protective devices, earthing, distribution equipment, and a changeover system or Automatic Transfer Switch (ATS). The ATS transfers the designated loads between the mains supply and generator, according to the system's design and operating sequence.

Other requirements may include fuel storage and supply, exhaust arrangements, ventilation, suitable foundations, noise control, and generator monitoring systems. Planning, safety, and environmental requirements should also be considered.

Once installed, the system should be commissioned and tested to confirm that the generator starts correctly, supplies the required loads, and transfers power reliably during a simulated mains failure.

What electrical infrastructure is required?

The precise requirements will depend on the generator's capacity, the building's electrical installation, and the equipment being protected. Cabling, switchgear, distribution boards, protective devices, and transfer equipment must all be appropriately rated and compatible with the proposed system.

The design should also account for starting currents, changes in electrical load and any interaction with existing UPS systems.

Can an existing generator be replaced without replacing the rest of the electrical infrastructure?

Yes. In many cases, existing cabling, switchgear, transfer equipment, and other infrastructure can be retained when replacing a standby generator. However, this depends on their condition, electrical ratings and compatibility with the new generator.

A replacement unit may have different power ratings, fault characteristics, control requirements or physical connections. Changes to the site's electrical loads or backup requirements may also mean that existing equipment needs upgrading.

A thorough assessment will establish which components remain suitable and identify any necessary modifications before installation begins.

The key is to assess the complete installation before specifying a replacement generator. This helps ensure that the new equipment integrates safely and reliably with the existing infrastructure while avoiding unnecessary replacement costs.

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