Low and extra low voltage electrical installations
Electrical installations at low and extra low voltage shall be installed in accordance with the requirements of the New Zealand Electrical Regulations.
During the construction of an installation, and at its completion, the installation work must be tested and certified. For those installations or part of installations recognised as having higher risk of harm or damage to property by reason of their particular characteristics, e.g. hazardous areas, electrical medical, mains, etc., an independent inspection is required.
Finally, the installation work can be permanently connected to a supply after the certification, testing, and safety verifications have been completed and a ESC completed for the connection.
Risk Category vs installation stage. Click on image to view full screen version:
- Warrant of electrical fitness
Required for certain installations (Reg 76 to 78)
Certificate of Verification (CoV) required if disconnection > 6 months
Unsafe works and installations
Regulation 20 defines electrically unsafe works and installations.
Works and installations are unsafe if:
- the characteristics of any fittings are impaired
- the conductors are inadequately identified (e.g. the neutral conductor must be black/black must not be used for any other conductor)
- the connections are not secure and reliable
- cooling conditions are impaired
- there is a risk of ignition (e.g. fittings subject to high temperature unguarded.)
- cables are not protected against the risk of damage or are bent beyond their design criteria
- there is insufficient space to work on the installations safely.
In addition, measures must be put in place to do at least one of the following:
- prevent accidental contact with exposed parts
- provide automatic disconnection of power if a fault arise that would cause injury
- prevent or limit (International Electrotechnical Commission shock current Standards) electric current passing through the body of a person on contact of any part of the works or installations.
Anybody who designs or supervises the design of, works, installations, fittings, or appliances must ensure that the finished design would be electrically safe.
Information on the technical requirements for construction of low and extra low voltage installations.
Electrical installations considered to be a high risk are subject to third party inspection.
Certain checks must be undertaken before connection can occur.
A person who owns or operates works, installations, fittings, or appliances must not use, and must not allow anyone to use, the works, installations, fittings, or appliances if they are electrically unsafe.