A cascade of power failures left internet users across Tauranga without service for around three hours on Sunday afternoon.

The fault, at Chorus' Cameron Road exchange, effected all fibre providers, says Full Flavour Ltd ultra-fast broadband manager Jesse Archer.

The Cameron Road exchange where the fault occurred. Photo: File.

It is believed to be the first time such an outage has occurred in Tauranga, and according to Jesse, it highlights a glaring weakness in Tauranga's telecommunications network.

'If a bomb were to strike the exchange in Cameron Road, the city's communications would be off for days if not weeks,” he says.

'It is like a single point of failure for the city.

'There's a room in that building where all telco providers, including our network, Spark, Vodafone and Trust Power, have their equipment. Basically, the power failed to everyone's equipment in that room including Ultra-Fast Fibre.”

Power to the room in question is understood to have been completely lost, meaning an outage for fibre customers across the city, with equipment showing a loss of signal.

'At the exchange, there is supposed to be an A+B power feed,” explains Jesse. 'That means if the A power feed fails for some reason, there is a back-up.

'There's a unit called a rectifier, which changes AC power to DC power to go into some batteries. It was a rectifier, one of eight, that failed.

'That caused a surge upstream to some sort of AC breaker that then tripped and cut the power for both A feed and B feed.”

Full Flavour Ltd have since asked Chorus why the battery backup didn't provide sufficient power between the time the rectifier failed and the electrician's arrival to resolve the issue.

They have also asked why was there no electrician available in Tauranga.

'We had to wait an hour for an electrician to come from Rotorua,” says Jesse. 'It was a three-hour outage and it might have only been a two hour outage. A technician from Tauranga could have got in there at the same time as we did.”

Providers such as Full Flavour, Ultrafast Fibre, 2degrees, Vodafone and others had staff attending the incident within 15 minutes of it occurring, he adds.

When contacted by SunLive regarding the outage, Chorus communications manager Nathan Beaumont said: 'We had a fault on our network yesterday which meant more than 1600 households were without services for about two hours.

'Chorus apologises to those impacted by the outage.

'Our first priority was to ensure the network got back up and running as quickly as possible. Now that that has happened, we are now investigating what why the fault happened and what we can do to ensure it doesn't happen again.”

Full Flavour is a local, ultra-fast broadband provider with its core network in the Chorus Exchange.