Bundling in panelboards

[ptonsparky]

Then you would really cuss me out if you ever follow behind me in a control panel.

Not so much if both ends are labeled and there is a current drawing. Otherwise snip, snip.

 

[jumper]

Not so much if both ends are labeled and there is a current drawing. Otherwise snip, snip.

Everything is labeled, drawings include full schematics, parts list, and point to point diagrams.

 

[ActionDave]

Everything is labeled, drawings include full schematics, parts list, and point to point diagrams.

And then I have to read all that and interpret it and get a headache, or I can cut the ties and tug on a wire to see where it goes cussing the whole time.:rant:

 

[jumper]

And then I have to read all that and interpret it and get a headache, or I can cut the ties and tug on a wire to see where it goes cussing the whole time.:rant:

You are prolly gonna want those schematics, 400+ wires in the panels.

 

[MAC702]

Then you would really cuss me out if you ever follow behind me in a control panel.

I simply cut them. And while the dikes are in my hand, I'll cut them all while I'm at it. And I won't put them back when I'm done.

So, you might do more cussing if you come back, though...

 

[tom baker]

One rule that would apply is 310.15 A 2, higher ampacity applies if the part with the lower ampacity is not more than 10 ft or 10%of the total circuit length.
I love cable ties. I use different colors for MWBCs

 

[brian john]

Not talking control panels were we typically lay out and bundle our conductors neatly.

In panels, if you use a cable tie with a mounting hole and make a loop (but not tighten it) that will keep the conductors in place, allow troubleshooting, allow future circuits and remain fairly neat.

 

[Skokian]

Bundleng = Bad for Power Wiring.

Bundleng = Bad for Power Wiring.

We made measurements of bundled -versus- spaced out wiring in large fire pump controller cabinets. These boxes were typically 80" x 72" x 12" (w x h x d).

The wires were sized per the free air temperature ratings in NFPA-70.

The bundled wires ran much MUCH hotter than the spaced out ones. Specifically, the temp. rise was several times higher.

The reason is that bundling does two things. It cuts the cooling area WAY down, and also causes mutual heating between the wires, or cables in our case.

E.g.: For wires used anywhere near their rated ampacity DON'T bundle. For control, signal, or other wires not near their ampacity, feel free to bundle.

 

[MAC702]

...Specifically, the temp. rise was several times higher...

Several times higher?

Temp measurements don't usually work that way.

Yes, knowing you had temps significantly higher is useful, but I don't think you meant to say several times higher, did you? That would be hard to do.

 

[kwired]

Several times higher?

Temp measurements don't usually work that way.

Yes, knowing you had temps significantly higher is useful, but I don't think you meant to say several times higher, did you? That would be hard to do.

Plus in a fire pump controller cabinet I wouldn't expect there to be much for loading except during a fire or during some sort of testing under real load.

 

[MAC702]

Seeing that post again with a fresh cup of coffee has cleared it up for me. He said the temp rise was several times higher, not that the temp was several times higher.

All seems right with the world. Nothing to see here. Move along.