Members of the Electrical Trades Union NSW at Transgrid will begin the industrial action from Friday, delaying planned maintenance and potentially affecting power outages.
It will include a one-hour work stoppage by all ETU members as well as six indefinite work bans by control room staff, who act as critical workers in the company's nerve centre.
ETU NSW and ACT secretary Allen Hicks said Transgrid can afford to pay its workers more, yet refuses to despite having an ongoing pipeline of lucrative work.
"Transgrid's insulting pay offer has left workers with no choice but to take industrial action that will affect billions of dollars worth of crucial renewables and transmission projects," he said.
"Of course, the company could resolve this instantly by returning to the negotiating table with a fair pay offer."
Transgrid operates and manages the high voltage electricity transmission network across NSW and the ACT, which it describes as the "backbone of the National Energy Market".
The company is also helping complete major transmissions project EnergyConnect, which will join the NSW, Victoria and South Australian energy grids, allowing for the sharing of power between them.
The ETU said it is committed to ensuring that industrial action will never endanger the public or workers and that resources are available to meet emergencies or natural disasters.
Transgrid has been contacted for comment.
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