It should be back in production this weekend according to Woodside.

In a statement to the media, the company said a "fault" occurred in the electrical system on board the Ocean Legend oil production facility. As a precautionary measure, all 18 personnel were evacuated by helicopter to the mainland.

"The relevant State and Federal Government authorities have been advised. There is no threat to the environment from either the incident or the decision to evacuate personnel," a Woodside spokesperson said.

The Legendre Field started in May of this year and pumps about 40,000 barrels per day. Woodside and Santos Ltd are the major partners in the field.