All pictures and information supplied by RODALCO:


The pics:










Thank you Ray!.

From the second pic, looks like some sort of fault has already happened in there, notice the blackening of the can to the right of the streetlight block?

Are those factory installed jumpers? If so they should have been adequate for the full rated load.

But I also see this stirring up the debate on bundling!!

I would have been wary of disturbing anything too.

No not as far as i'm aware off mxslick.

These cables are NOT factory installed.

These DIN racks are assembled and put in on site by whoever gets the quote for the transformer install.

These cables were obviously under rated and should have been upgraded when other DIN fuses were loaded to accomodate new circuits.

In stead of doing it correctly the first time, Jumpers should be adequate for the maximum continuous load + 20 % from the transformer.
In this case cables rated at 800 Ampères should have been fitted. Better to feed the busbars from two sides as well.

Note the red colour sleeve by the bushing which has split from heat transfer from the copper conductor.

Bundling too, cables close together can't dissipate heat as effective. Better to use insulated spacers in between them.

Looks like the ampere readings you took are obviously accurate, one look at those jumpers and you can see that the red phase is definitely the high leg. Way to go on diffusing that ticking timebomb Raymond.

What's that small wire that appears to be loosely attached to the black bus(position #4)?

steve

Steve,
That would be a temporary neutral.

A temporary Neutral stamcon

That one and the red phase one with the airborne HRC fuse are driving the (temporary) timeclock,
which drives a streetlight contactor below the five 16 amps HRC fuses.

Our Neutrals are Black here in NZ.
Good skills though Ray, leave the thing to cool down before doing anything with it.
I see the heat-shrink cover has split, it takes a bit to do that.
One of your own time clocks?.
I note the RF label on the clock panel.
One thing I have noticed since leaving the PoCo here in Ashburton, is that sometimes on Monday nights, the Street-lights are out.
Not one block, but most of the town.
Un-real!.

Well spotted Mike,
I use RF 9xx asset numbers on the clocks and an XL spread sheet to keep track of my clocks, platform numbers, address etc.
That is one of the newer ones. Late 1988 Maxirex BQT from Germany.

A lot of clocks I use are 40 + years old with full clock work motor driven mechanisms. (Landis&Gyr, AEG, Sangamo).

Mike, the POCO obviously needs you back and is lacking qualified staff to deal with the streetlights matter.

edited for typo's RF.

[This message has been edited by RODALCO (edited 09-05-2006).]

I know this is minor compared to the problem at hand but i dont like the zipties, too tight. Just makes the heating worse.

Electrictim,
Welcome to ECN, mate!.
Not a minor thing at all really.
Perhaps a round tubular spacer under each cable tie (in the middle of the bunch of wires) would aid air circulation?.
Ray,
Is that wire used for the jumpers, that really finely stranded stuff (like welder secondary cable) or ordinary copper cable?.
Just curious.


[This message has been edited by Trumpy (edited 09-22-2006).]

Just reading through some of the older threads.

That transformer was upgraded to a 750 kVA, which caught fire on the LV rack about a month ago. ( nov 2007 )

I see if i can find some photo's from that fire.

Now a 1000 kVA TX is installed here.

The silly thing is with this so called de regulation of the electrical industry is feeding these industrial sites via a 185 mm² Al ringmains. The developer puts in the minimum required and problems start almost immediately when the loads builds up in the area.

In the old POCO days, any new supply over 160 Ampères will get an HV supply with a TX on site.

We have had various LV pillars melt down here because of overloading.

Regards, Raymond

Deregulation is not to blame. Didn't you here? deregulation is a good thing. All kidding aside, professionalism and good work ethics do not require regulation. Greed breeds regulation