Sexual - Still makes me tingle

[a1guvner]

Presented with no comment.

 

[Knobhead]

Think the argument is 50/50 about the clamping the cables down although it gives that professional finish but must agree with everyone else ... heat shrink a must - tape is rough and you rely on the tape gum for the life span of the equipment although it poses not real safety risk a few yrs down the line your tape could be pealing and giving your work a poor reputation to anyone that follows you. Having said that if all your been pulled for is lack of heat shrink and a debatable lack of fixing then I wouldn't fret too much and take the advice on board.

Just spotted this post DW.

The jury has returned with a verdict. Have a look elsewhere for a topic on transformer tails. In particular the bit about magnetic reaction under fault conditions. It’s not a case of they look better, it’s a matter of safety.

 

[HandySparks]

Just spotted this post DW.

The jury has returned with a verdict. Have a look elsewhere for a topic on transformer tails. In particular the bit about magnetic reaction under fault conditions. It’s not a case of they look better, it’s a matter of safety.

Cleated cables on ladder under fault conditions:
https://www.youtube.com/watch?v=YZiTmk7cDrM

 

[Silly Sausage]

https://www.youtube.com/watch?v=HmnrJa7Zk0A

5 minutes onwards to see what happens with weak cleating!

 

[Knobhead]

Cheers HS and Archy, both of those clips prove the point rather well.

 

[Maddison]

not the kind of thing you want to get wrong...

 

[Knobhead]

One poor sod got chopped in half by trench cover plates being thrown in the air.

That was back in the 80’s, a couple of months before I started re-cabling a substation. For some strange reason we had a bit of a rethink about the job. I’ve had a bee in my bonnet ever since.

OK you can use the reasoning, what are the chances of it happening?
Quite high, the substation above one of the mates let a ¼” chequer plate drop in to the trench. There was 28x500mm cleated to the sides, fortunately it only skinned the outer serving off a few of them. Had it gone through the insulation there would have been 4x1000KVA 11/.433KV transformers feeding the fault.
Can’t say I was too happy, I had to repair the cables. A week after we’d put them in.

 

[Guest112]

Tony, in the op pictures, do you think that not cleating the spaced cable vertical drops could be dangerous under fault conditions in this situation? The reason I ask is because they are't run in trifoils but are rather entering up vertically spaced apart?

 

[Knobhead]

The distance between them is about the only saving grace.

Depending on how they are fastened in the trench has a bearing on the drops from the terminal box. If they can move in the trench then damage will be done to the terminals.

I would put them in single cleats anyway.

 

[Tiny Spark]

Damn never seen anything like that!
Gives a good appreciation of why though!!

 

[Knobhead]

Makes banjos seem insignificant doesn’t it.

 

[Tiny Spark]

Well I knew big cables were rated for big fault current but I never realised they could react like that!!
Though yes It would make many things seem pointless and insignificant.
Its funny I have been in a few subs and allways given the stuff a wide birth when I didnt have to be near it but think ile have to stay clear of the ladder racks to now LOL

 

[Silly Sausage]

Makes banjos seem insignificant doesn’t it.

It shows the power of an invisible magnetic field. Awesome!
One reason why electricity is such a fascinating subject.