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From Stuff:

Meter blast sounded like bomb:

A power meter board explosion which caused a fire at Parklands shopping centre was so loud it sounded like a bomb going off and was so hot it turned steel to liquid.

Riddick Electrical owner Blair Riddick, whose company had been contracted to rewire the building, said the intensity of the electrical fire was so great it warped steel roofing beams and turned a 4mm thick meter board cover into molten steel.

"People said it sounded like a bomb going off," Mr Riddick said.

The repair job would be massive, he said.

All but two shops affected by the fire on Friday were back up and running yesterday and the landlords were keen to let customers know.

Westwill Properties director Glenys Waters said there were very few customers at Parklands yesterday despite all businesses opening, except for the library and the supermarket.

"People aren't around today because they think everything is closed," Mrs Waters said.

Builders and electricians had been working around the clock to repair the fire damage and set up two generators, she said.

"The electricians have been brilliant doing everything they possibly could."

Supervalue supermarket, which was extensively smoke-damaged, would take at least two weeks to reopen, she said.

"It's a mess. She has to start from scratch, there's nothing she can salvage," he said.

Virtually 100 per cent of stock would be thrown out due to smoke damage, she said.

"Smoke leaves an oily residue and you can't get rid of it."

Puke Ariki manager Bill Macnaught said the library was expected to open next week.

"We have some water damage to the carpet and a bit of smoke residue in the library, but the big problem is the lack of power," Mr Macnaught said. No books were damaged in the fire.

Books that were borrowed from the library could be returned to Puke Ariki or any other library in the district, he said. As of yesterday all other shops were operating within their normal working hours.

Four fire crews were called to the centre on Friday afternoon after the supermarket power meter board malfunctioned.

Trumpy:

Sounds like a really serious fault within a piece of switchgear. Any info on a cause?

Hi John,
I can only guess at this stage of the game.
It sounds to me like the Power Company had long since upgraded their mains and transformer gear, but the equipment that was still in place at the shopping centre, had a lower PSCC limit than the NEW fault current level.

It failed to handle the new fault level and pretty much blew itself to bits.
BTW, this probably has very little to do with metering at all, as the meters that would have been installed would have been fed via CT's.

I would imagine what actually exploded, would have been the Main Circuit Breaker feeding the whole shopping centre, given that all of the shops lost power and that the blast was so large.

This is however only as I said, a guess.

Trumpy:
Thank you for the above. That's what I thought!

Within your comments you used 'PSCC' which I think is your terminology for 'Fault Current' on this side of the world.

There's another thread here with a deep debate on terminology for Fault Current (KSCA/KAIC/etc) which was getting testie; have you seen it?

Take care & stay safe!

Yes John,
PSCC= Prospective Short Circuit Current.

Mike.,

Just wondering when any time your POCO do the upgrading their system do you have to warn the customer of new level of PSCC level ?

And what the typicl PSCC level you have in your area ?

Merci.
Marc