Three days without power, three neighbourhoods affected, one substation to blame

Boskruin, Bromhof and parts of Randpark Ridge have been without power since Saturday (31 March) due to a power trip at Hawken switching station.

Ward 134 Councillor Wendy Alexander explained the issues faced at the substation are multifaceted.

She attended a site visit with Ward 102 councillor David Potter, MMC Nico de Jager and City Power officials.

“Preliminary testing on all distributors were conducted and all tested clear. Attempts to restore were unsuccessful as the trip occurred again whilst load was at about 20 per cent,” said Alexander, adding that this tripped transformers two and four on the Eskom side but were later restored at about 1.30am on 1 April.

Alexander said the protection and testing teams had been on site and thorough tests were carried out on every cable, breaker and relays at Hawken “The team also replaced batteries at the station, which were stolen.”

Further tests done in the early mornings of 2 April indicated that the second feeder cable from Randburg to Hawken had been stolen in the tunnel and teams have been dispatched to investigate the extent of the damage and replace what was stolen.

Alexander said the following will be done as a way forward:

• A generator is ordered to charge new batteries at Hawken substation
• Testing of the breaker and the current transformer (CT) on the Hawken distributor at Randburg substation.
• Replacement of stolen cable in the tunnel (not mission critical as there are two feeders)
• Possible overriding of overcurrent protection on the Hawken Feeder at Randburg to be considered by Protection, should the CT be faulty.

City Power has confirmed that they are doing their level best to restore power to Boskruin and surrounding areas.

According to the power utility, supply may come on and then trip again as part of the restoration process.

It is suggested that everyone unplug all their appliances.