Percent Fill

[gabe044]

I'm trying to get the percent fill of a cable tray that contains m/c cables <4/0 AND >=4/0 and one that contains s/c cables >1000kcmil AND 250-1000kcmil. I tried calculating the total diameter and then finding the area of that but it turns out to be a huge number and I get well over 100% fill.

Thanks

 

[gabe044]

Should I just treat the larger cables the same as the smaller ones and add up their individual areas and then sum up ALL the cable areas?

 

[LarryFine]

I tried calculating the total diameter and then finding the area of that but it turns out to be a huge number and I get well over 100% fill.

Wrong.

Should I just treat the larger cables the same as the smaller ones and add up their individual areas and then sum up ALL the cable areas?

Right.

 

[gabe044]

ok. then do i divide the total areas by the allowable fill area of the tray or by the acutal total area inside the tray

 

[gwpowell]

There are some very good cable tray sizing documents on B-Line's website (www.b-line.com) and also a NEMA publication (VE 2-2000) that are very helpful in designing and installing cable tray. I would attach these documents, however the file sizes are too large.