The Economic Regulation Authority has ruled Western Power did not contravene their electricity distribution licence obligations in April when two life support equipment customers went without power for a short time.
Western Power contacted the regulator on April 17 to notify them of a possible breach of the Code of Conduct for the Supply of Electricity to Small Use Customers 2014.
Clause 7.7(4)(b) of the code is classified as a type one (considered the most serious and therefore immediately reportable) obligation for electricity distribution licenses on the basis that the consequence of a contravention would endanger, or threaten to endanger, the safety or health of a person.
The two life support equipment (LSE) customers experienced interrupted power supply for approximately five minutes while Western Power undertook a planned interruption.
Western Power advised the ERA that it has initially intended to include the premises of the two LSE customers in the area affected by the planned interruption.
Accordingly, Western Power notified both customers in compliance with the code of conduct and obtained their acknowledgement that they had received the notification.
After notifying the customers, but before undertaking the planned interruption, Western Power reduced the area that was to be affected by the interruption so the premises of both LSE customers now lay outside that area.
The intention was to perform a switching action immediately prior to the commencement of the planned interruption that would keep the two LSE customer and other customers in the same locality, connected to a supply for the duration of the planned outage.
An error in the switching schedule resulted in the brief interruption of supply to the two LSE customers.
Western Power staff quickly became aware that the supply to the LSE customers had been unintentionally interrupted and acted to restore supply.
Because the two LSE customer premises lay outside the area covered by the planned interruption, the ERA does not agree that Western Power contravened clause 7.7(4)(b) of the Code.
Instead the supply interruption to the LSE customers should be recorded as an unplanned interruption that was an unintended consequence of the planned interruption.
The ERA noted in its report that Western Power has taken appropriate actions to reduce the risk of a similar set of circumstances.