SYDNEY, April 28, 2009 (AFP) - Australian Fashion Week ground to a halt, workers had to be evacuated and people were trapped in lifts on Tuesday 28 April after a power failure in central Sydney.

An aerial view of Sydney. Australian Fashion Week ground to a halt, workers had to be evacuated and people were trapped in lifts after a power failure in central Sydney (AFP/File/Torsten Blackwood)

Hundreds of expectant guests were gathered at the harbourside for an Australian Fashion Week show when the lights went out, the third major outage to hit Sydney in a month.

"I'm just glad it didn't happen during the show," designer Nicky Zimmermann told Australian Associated Press.

Businesses in the city's north were blacked out for almost an hour after a fault in a major power supply cable triggered an automatic switch-off just after the morning rush, authorities said.

Traffic was also disrupted as dozens of traffic lights failed and police said they had to rescue workers from lifts in two city office blocks, while 400 staff were evacuated from a third.

In late March a widespread blackout plunged the city into peak-hour chaos for more than two hours, forcing the cancellation of shows at the iconic Opera House.

Energy Australia spokeswoman Kylie Yates said a fault in the automatic shut-down equipment was to blame.

"This equipment is designed to shut down a part of the electricity network when a fault occurs, and this equipment is shutting down a wider area than we would expect," Yates said.

"So that's something we're investigating, and have been investigating as a priority."