Supply
Quality of Supply
Proposal
- To continue existing Regulations (53) Voltage, (55) Frequency, (56) Quality of Supply, (57) Change in supply characteristics, and (59) Keeping records and plans.
- To continue existing Regulation 58, with some clarifications.
New Zealand has a supply voltage of 230 V. Variances can come from interferences from nearby installations, the operation of the electricity supply network, and from environmental factors, such as weather. As such, there can be no guarantee of a variance free supply. However, it is important that the variances are kept within tolerance levels to minimise any safety risks that may arise.
Accordingly, it is proposed to carry forward to the electricity safety regulations similar regulations to:
- Regulation 53: which specifies the voltage of electricity supplies to electrical installations, and the margins of variability that may be allowed;
- Regulation 55: which specifies the frequency of electricity supplied;
- Regulation 56: which addresses situations where equipment unduly directs major levels of harmonics into the supply system, and these harmonic voltages interfere with the satisfactory supply of electricity to, or impair the safety or operation of electrical fittings of, other electricity users.
- Regulation 57: which specifies that no person supplying electricity or line function services may alter the electrical characteristics of the supply in a way that may cause danger, and must ensure they take reasonable steps to ensure the prospective fault currents are limited to reasonable levels.
- Regulation 58: which specifies that every owner of works must keep records and plans in order to enable that owner to readily locate any fittings of those works.
It is also proposed to carry forward Regulation 58 (Electrical Interference with Telecommunications lines, etc) but to clarify its intent along the lines:
- that in addition to construction of telecommunication lines and electrical works and installations, the alteration and maintenance of these structures can also produce electrical hazards; and
- by inserting the appropriate descriptor (either "telecommunication" or "power") before the phrase "lines, structure, device or thing". Currently there is confusion as to which lines are being referred to.
The existing Regulations also include in the quality of the supply of electricity section other regulations that it is proposed are better addressed under other parts of the new regulations or in other forum as follows:
- Regulation 52 (3): which allows for a 10 ohm maximum for total system neutral impedance to earth, yet 52 (5), allows that maximum to be exceeded where it is impractical. The level of 10 ohms does not guarantee a safe earthing arrangement. It is proposed to require earthing arrangements to be safe, rather than specify any particular requirement. (See discussion under General Electrical Safety Requirements.)
- Regulation 54: which specifies the margins of error for meter accuracy. Meter accuracy is covered by the Electricity Commission Rules and it is not appropriate to have duplicate requirements in regulations.
Questions
Are these the right quality of supply matters to cover in the regulations?
Are there any other quality of supply matters that should be covered?
Back to Top