Sydney commuters have been urged to avoid the train network unless absolutely necessary, due to ongoing impacts from a power issue on Tuesday that cause chaos for hundreds of commuters during peak hour.

The disruption on Australia’s busiest suburban network was triggered when a live overhead wire came down onto the roof of a train about 2.30pm Tuesday, trapping passengers on board, cutting power and causing widespread delays.

WATCH THE VIDEO ABOVE: Sydney commuters face more train chaos after network collapse.

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NSW Transport Minister John Graham described the situation as dangerous, saying a 1500-volt power connector was sitting on top of the train carrying 300 passengers about 20 metres from Strathfield station.

“This is a very serious incident, right in the heart of Sydney’s train network,” Graham told ABC News.

The power issue impacted all lines bar the T4 South Coast and Central services, with significant delays.

Transport for NSW confirmed that services were still impacted on Wednesday morning.

“Most lines will be impacted this morning due to power supply issues at Strathfield,” it said on X.

“Trains will operate, but services will be reduced and will not run to a normal timetable. Please delay non-essential travel.”

There will be limited shuttles available, it later said in a statement.

“If passengers must travel, plan ahead and allow extra travel time. We have trains running on all lines, but at a reduced frequency.

“Sydney Trains teams have been working hard overnight and have removed a defective train and completed repairs to the overhead wiring that caused major disruption on the rail network yesterday.

“Teams are completing the final inspections before we reinstate the power later this morning to allow all six tracks from the west through Homebush to operate services.

“Sydney Trains apologises again to passengers for the inconvenience of the continuing disruption.

“It’s expected the work will be completed later this morning and we will look to transition to normal timetabled services for the afternoon peak services.”

Train platforms were overwhelmed with commuters stuck due to delays on Tuesday. Credit: 7NEWS

Passengers were evacuated from a train stranded on the tracks at Strathfield. Credit: 7NEWS

On Tuesday night, Transport for NSW activated its agreement with Uber to prevent unreasonable surge pricing during the incident and its flow-on effects.

Train platforms were overwhelmed with commuters stuck due to delays, with two trains stuck on the tracks.

A commuter told 7NEWS he had been trapped in a train carriage for almost three hours without air conditioning.

“We had a sudden turn or something like that, and then the train stopped all of a sudden and the lights went off — it was not bright as it usually is,” Bishal Dangi said.

“It’s suffocating. All of the people are asked looking for answers.”

But Dangi couldn’t leave the train.

“They said they were going to disembark us,” he said. “OK, at least if you could do that, I could get to work on time. I could take an Uber or something. I have no option. I can’t get off. There’s nowhere to go.”

Passengers could not be evacuated until the live wire was safely isolated.

Collins apologised for the lengthy process, and stressed the seriousness of the situation.

“If you get very near or touch wires with that amount of voltage and amperage, it will kill you straight away.”

- With AAP