How do you determine cable cleat spacing on a cable sealing end structure?

[electrical429]

Three structures, each housing one single core cable.

 

[waross]

I know that your post makes perfect sense to you, but the rest of us need a couple of more details.

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Ohm's law
Not just a good idea;
It's the LAW!

 

[cuky2000]

Waross is right, additional clarification is needed.

In general, cable cleats are spaced to control the electromagnetic forces generated by the peak short circuit current. This can be determined by applying The Lorentz Force Law between conductors, as shown in the illustration below.

The force is inversely proportional to the cable spacing and should limit by the withstand capability of the equipment cable termination assembly.

Hope this help to guide the clarification for this post

 

[electrical429]

In below example distance between cable cleats is 500mm. The cable is 1000mm2.

What distance would you have for 630mm2 cable. Above image shows one cable sealing end structure. We have 3 in total (1 per phase). Distance between each other is 3m. I have calculated that short circuit force on the cables will be 0.666667 kN/m. CSE structure height - 3m, therefore total force = 2kN. Proposed cleat performance data below:

Should I be looking at lateral or axial load? In any case its much higher than 2kN, therefore technically we can install only one cable cleat per cable sealing end structure? Do cable electromechanical forces play a role here like thermal contraction and expansion? Do we need to install more than one cleat? Will cable electromechanical forces affect cleat spacing or I only need to look at short circuit forces and can install any number of cleats between 1 and however many fit on CSE structure and it doesn't matter what the spacing between cleats will be?