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#122780 01/12/06 10:03 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Pics and info submitted by RODALCO:

From this thread .
Quote
These photo's were taken today after we fixed a simple streetlight fault at Lincoln Rd Henderson. The job was put on hold as usual and the council jumping up and down. The lights affected were near a park and pub, The Lincoln Green.

Quote
1st photo: Cable damage was done by directional drilling for upper conduit.

[Linked Image]


Quote
2nd photo: Closer up look. This is the twin & pilot 16mm² cable. (only red and black are used here)

[Linked Image]

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3rd photo: Red paint marks identify the fault location, done with Magpie. Hole nearly 1 meter deep.

[Linked Image]

Quote
4 th photo: Finished job, new piece of cable inserted and heatshrinked with Raychem heatshrinks.

[Linked Image]



[This message has been edited by Trumpy (edited 01-12-2006).]

#122781 01/12/06 10:57 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
I'll tell you one thing Ray.
About 3 years ago when I first went back to Faults work down here, the local RSA were doing some extensions.
I was sent there to mark out the cable runs for the excavator operator.
I knew where these cables went, because we laid them 7 years previous.
I sprayed the area where the cables were and thought nothing more of it.
I got talking to a few of the ladies and had a cup of tea (10am) when there was an almighty bloody explosion from outside.
The guy had gone over my spray marks and torn up a Neutral-Screened cable that fed the Supermarket next door.
It was still crackling when I got out there.
This was the largest sized copper cable that we use and we had to order in a jointing box for it.
Anyway that was probably a good thing because later on in the day, the guy hit the other side of the cable on the other side of where the foundation was going to be.
I haven't seen that excavator operator since that day.

#122782 01/12/06 02:45 PM
Joined: Dec 2005
Posts: 869
Likes: 4
R
Member
Thanks Mike for posting the photo's.

I think sometimes a photo says more than 1000 words and provides hopefully a learning tool as well for other members.

In the greater Auckland area, there is at the moment a lot of directional drilling going on for fibre optic cables and new OHUG work. Streetlight cables get often damaged because they are off during the day. The faults become apparent when sections of lights are not working at night.

Also very few section fuses are used (poor planning by projectmanagers to save a few bucks) and large area's will go in the dark.


The product of rotation, excitation and flux produces electricty.
#122783 01/13/06 04:56 PM
Joined: Dec 2001
Posts: 2,498
T
Member
Street light faults usually knock out half a district at once here, which could mean areas of roughly 1 square kilometre or even more (densely populated). In summer or early fall there was an attic fire in a 4-storey-building several hundred metres from my home. I think it's 4 1/2 blocks from us. For the fire brigade to get up there in the not too wide street (2 narrow lanes, parking and side walk on each side) they had to cut the overhead cable for the street lighting. It looked impressing! It was dead but only the mechanical reaction... the remaining lights flexed back a good metre when the triplex (2 phases switched individually for switching off half of the lights at midnight + neutral, 230V, no ground as all street lights are class II) was cut. That happened in the afternoon (I think it happened around 5 PM) and knocked out half the district until 8:30 PM. Yesterday we had another failure of that dimension or even bigger. Me and a friend talked to the faultsman a little when he was done. I don't remember all of it and some of his explanations were somewhat blurry, but apparently the line wasn't deenergized but only switched off during daytime. The automatic start tried to switch on, detected a fault, tried again and again and knocked out larger areas with each try.


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