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#141151 06/16/04 05:31 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Well,
A handyman that I know, will be looking for a new job, can you accomodate him?.
New Zealand Fire Service Ashburton turned out to a house fire this afternoon.
Nothing un-usual really, except that this hasn't even been lived in yet.
I was the Officer on the first responding Appliance and when we got there, the thing was going well.
We were met by the said Handyman at the gate.
He was distraught(sp?).
New house, grounds all landscaped, the whole project cost NZ$2.1 million.
But what caused all this, is this, according to the H/man.
  • At about 10am he was in the Garage and noticed a humming sound coming from the Main Switchboard, he then discounted it as normal, as he said Contactors always hum.
  • About 11:30 the first pole fuse blew.
  • About 11:35 the second pole fuse blew.
  • About 11:40 the third pole fuse blew,
    (in sympathy of the other two)
  • Around 11:50, with the thought of no power crashing the pre-installed C-Bus Automation system, the handyman, then proceeded to climb the pole on the boundary, remove the standard BS 88 HRC fuses and fit wire to the holders and replace them.
  • 1200, power back on, C-Bus system still working, problem alleviated.
  • Around 1300, the Handyman notices smoke and flames coming from the other side of the building (he was doing the gardens around the back)
  • 13:25 Ashburton 621 and other appliances arrive.
  • 13:30 Second Alarm is called, bringing in appliances from Methven, Hinds and Rakaia.
  • Police are responded, with the information at hand.

We lost this house, a 7 bedroom, 2 living area, 2 studies building.
And nearly lost 2 BA crews in the thing.
We had to just stand back and put the Deck Monitors on the thing.
So sad to see, a well built building be reduced to ashes, because of one guy's stupidity.
Mind you, he is 55. [Linked Image]

Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
I'm going back with Fire Safety in the morning, but I don't think that there will be a lot to see.
We tried to douse the flames, but even that was a task in itself.
Personally, I am glad I am not the family that looked to move into this house next week. [Linked Image]

Joined: Aug 2001
Posts: 7,520
P
Member
Quote
Around 11:50, with the thought of no power crashing the pre-installed C-Bus Automation system, the handyman, then proceeded to climb the pole on the boundary, remove the standard BS 88 HRC fuses and fit wire to the holders and replace them.

[Linked Image]

Why do so many people seem to think that we use fuses just for the fun of it?

Joined: Aug 2002
Posts: 1,691
S
Member
I'm surprised the handyman admitted to his stupidity. [Linked Image]

What can happen to him now? Will he get sued or thrown in jail because of this? What in blazes possesed him to do that, much less even climb a pole?!!

Joined: Oct 2003
Posts: 289
:
Member
What does it mean, that 3 pole fuses blew.

3 phases, or was the fuse replaced 3 times?

and what was the fault in the end?
When there was a short, wouldnt there have been _big_ sparks when resetting the fuse/wire?

[This message has been edited by :andy: (edited 06-16-2004).]

Joined: Feb 2004
Posts: 1,438
Member
pauluk wrote:

Quote
Why do so many people seem to think that we use fuses just for the fun of it?

Amen to that! not to mention thinking changing the size up a notch solves everything! [Linked Image]

It's terrible to hear about this home being destroyed! While the handyman/landscaper/whatever made a seriously stupid move, at least he stuck around to face the music! Usually they'll high-tail it outta there, maybe calling the fire department on a payphone on the way! [Linked Image]

This guy is actually seriously lucky he wasn't killed stuffing wire into those fuse holders! I'm assuming there was some kind of fault condition happening... I'll second Andy's quiere about the big sparks! I'd think he would've gotten a face full of light & molten metal when he completed that circuit again! [Linked Image]

-Randy

Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Just an update guys,
I have it in good faith that this case will be going to Court, between the Owners of the property, the PoCo and the New Zealand Fire Service, this guy has a HUGE case to answer.
There was an incident today where 2 lawyers for the Defence were sent away from the scene, for trampling on evidence, literally jumping on the old Panel. [Linked Image]
I'll keep you guy's posted as to the progress on this one!. [Linked Image]

Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Andy,
Just a reply to your question that warrants an answer.
The house was fed with 3x 16mm2 Neutral-Screened from the pole in question.
Cable like this can be fused at 63A per phase, as a rule of thumb, that is the maximum current draw that N/Screened will handle buried direct.
What happened though, was the EC that installed the Service Line, ran the thing in 100mm Orange PVC Conduit (which personally I don't blame him for doing, considering it ran under several gardens on the way to the Main Switchboard) and through the concrete pad that the house was built upon.
Now having said that, any person that knows anything about Underground Cables, also knows that when you run a cable through Conduit, it has to be de-rated by a certain factor.
Length of run in this case gave a derating factor of 10% (0.90).
But the one thing that sets this incident apart from any other that I have seen is this:
  • 3 fuses blow at 5 minute intervals,
    Sure they were originally fused with 50M63 links(gM)
  • From what us Fire Officers can tell, the water pump was faulty, hence the humming Contactor.
    Tests concluded that the Pressure switch was stuck shut, it had been like this for a week or more.
  • Also what we were not looking for, but found anyway, was the fact of the Underfloor heating system had a resistance of 100 ohm to Earth, we can't be sure, but it could have had something to do with the fire, considering evidence from a PoCo inspector saying that the Afternoon Boost was on at the time that the fire would have happened

Joined: Oct 2003
Posts: 289
:
Member
so its an unlucky meeting of a few different faults [Linked Image]
bad story.
was that a wooden house?

Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Andy,
Invariably the majority of our houses are of timber-framed construction, with a Brick Veneer layer over the outside.
And the use of a timber floor has been thrown out, in favour of Concrete slabs, where everybody wants Underfloor heating elements installed before the concrete is poured over the top.
Just a note about these systems, you'd be suprised how many houses here had these U/F heating systems installed when the house was built, but the elements have been blown up by voltage surges, caused by nearby Lightning strikes on overhead lines.
After that happens, that's it, you can't use the system again.
And with the majority of the Wire-pullers, we call Sparkies here, not knowing what a Surge Diverter is, or even how to install one, this just makes the situation worse, as the Manufacturer of the most commonly installed system here stipulates S/D equipment to protect the U/F elements, most Sparkies just thumb thier noses at that idea. [Linked Image]

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