Power Outage – Wednesday January 9, 2013
12:00 Noon to 7:40PM
On Wednesday January 9th at approximately 12:00 noon, Grimsby Power’s protection systems detected a feeder fault and isolated the feeder from its load. This resulted in the loss of supply to one of its four main feeders causing a power outage for approximately 2900 customers. The approximate outage area included the south-east and south-west area above the escarpment and areas south of the South Service Road between Park Road and Robinson Street. This was a significant outage and in fact the longest large scale outage since the wind storm of April 28, 2011.
Crews were dispatched immediately to patrol the lines to identify the nature of the fault. After approximately 1 hour of patrolling a fault was found caused by an animal contact. The fault was repaired and an attempt to energize the circuit failed due to another fault elsewhere on the line. At this point, crews began to sectionalize the feeder in an attempt to restore sections of customers, and to locate sections of the feeder with further faults. As a result of this sectionalizing, second and third faults were found, both of which were caused by defective equipment. These faults were repaired and the power was fully restored at 7:40pm. In every failed attempt to restore the feeder, all customers who were previously restored would have been without power again for short periods of time. In all, eleven attempts were made to restore power to the feeder.
The nature of this event is very uncommon on Grimsby Power’s distribution system. Normally faults are readily identifiable and visible to the eye, and often customers will call in with evidence which will lead crews to the area of the fault. Examples of this are trees or tree branches on lines, broken poles, downed wires, vehicle accidents, and open line fuses to name a few. However, in this case, no customer information was available and each of the faults was not visible with the normal line patrolling methods. A slower more detailed inspection at each pole was required to identify these faults. This takes much more time to complete, thus lengthening the duration of the outage.
Many customers who attempted to call the office found the lines with a busy signal. High call volumes exceeded the capacity of the phone system. GPI’s risk analysis process identified this as a significant risk to good customer service. To correct this risk, Grimsby Power is currently in the process of updating its telephone system. This equipment was installed in late 2012 and will be fully functional in the next few weeks. The new system will enable callers to be placed into a phone cue instead of receiving a busy signal and it will enable staff to place current outage information in the message stream of the phone system.