Horizon Power :: Our service to you

Quality
Our Network asset must be Fit for Purpose to supply quality electricity to our customers, in terms of voltage levels, frequency, rapid fluctuations (flicker) and harmonics.

Specific Quality service levels details are:

Voltage limits
Voltage limits are as set out in Electricity Act 1945, section 25, specifically:

The Low Voltage Distribution System (415 V phase to phase) shall be maintained within the following voltage limits: +/- 6% under normal conditions, +/- 8% under maintenance conditions, and +/- 10% under emergency conditions.

The High Voltage Distribution System (6.6 kV; 11 kV; 22 kV or 33 kV) and High Voltage Transmission System (66 kV; 132 kV or 220 kV) shall be maintained within +/- 10% of the respective nominal voltage levels.

A recent European Standard EN 50160 sets similar standards but includes duration limits of the deviation. (These standards have not yet adopted in Australia)

In the absence of continuous voltage monitoring at network extremities voltage limit deviations are measured and reported as power quality complaints received that are resolved by network upgrades. Continuous monitoring, via tools such as Smart Meters, will be implemented as soon as practical, to provide a pro-active response to voltage deviation, possibly to satisfy the EN 50160 standard, which may be adopted by Australia in the near future.

Frequency
The frequency tolerance limit for the NWIS is 50 Hz +/- 0.4 Hz. For remote systems supplied from diesel power stations owned and generated by Horizon Power, the frequency tolerance limit is 50 Hz +/- 1.0 Hz.

Voltage Fluctuations (Flicker)
The voltage fluctuations which occur at the customer’s Point of Supply shall be within the limits as set out in AS/NZS 61000.3.3:1998 for households (and similar) electrical appliances and AS/NZS 61000.3.7:2001 for industrial equipment.

Harmonics
The harmonic voltage and current distortion shall be within the limits as set out in AS/NZS 61000.3.2:1998 for households (and similar) electrical appliances and AS/NZS 61000.3.6:2001 for industrial equipment.