Vertical Straight Cable Tray Support Spacing

[ThePunisher]

I could not find the clause in NEMA VE-2 that states the maximum support interval (spacing) for vertical straight cable tray runs.

Can anyone refer me to any reference that may help determine the spacing required?

Thanks

 

[7anoter4]

IEEE 690 "Standard for the Design and Installation of Cable Systems for Class 1E Circuits in Nuclear Power Generating Stations" indicates:
12.5 Requirements for Supporting Cables in Vertical Runs
" b) Vertically run cables shall be secured, as required, by support devices installed at intervals in the raceway systems. In vertical trays, cables shall also be secured at intermediate locations as necessary to keep all cables completely within and secured to the tray."
So, it is no indication what could be the safety interval to support the cables in vertically run.
IEEE Std 525-1992 "Guide for the Design and Installation of Cable Systems in Substations" indicates:
10.2.2 Supporting cables in vertical runs
"Cables with copper conductors, regardless of their voltage class, installed in vertical runs should be supported in accordance with the following [attached a table].
Recommendations for supporting special cables such as armored, shielded, coaxial, etc., should be obtained from the cable manufacturer."
But, better you have to take the Grips Manufacturer recommendations. See [for instance]:

http://www.afielektrik.com/PDF/urunler/HUBBELL-WIRING/T.pdf

 

[ThePunisher]

Thanks Zanoter4, but my query is regarding the interval spacing of supports on vertically mounted straight section of cable trays...not the cables.

However, NEMA VE-2 section 4.3.1 states that” The support span should not be greater than the straight section length or as recommended by the manufacturer, to ensure no more than one splice is located between supports”

Although the figure was showing horizontal run, I believe this would also make sense for vertical runs.

Would anybody agree?

 

[7anoter4]

A cable riser usually is mounted on the floor as per NEMA Standards Publication VE 2-2001 CABLE TRAY-TO-BOX/FLOOR SPLICE PLATES Figure 4.16A.The maximum height according to Manufacturer Catalogue it is 20 ft. If the steel cable tray is 6 inches depth [14 gauge hot-dip galvanized steel] will be self standing. But against horizontal forces it has to be fastened to the wall or column as per Figure 4.9C [for instance].In any case the weight of 20 ft length of all cables will be hung in this section will be over the limited force recommended by manufacturer.
In a complex riser installation a static [may be dynamic] mechanical calculation has to be done taken into consideration all the static weight and dynamic forces of thermal expansion and earthquake.
See [for instance]:

http://www.niedax.de/ext/brasil/pdfs/Niedax-KR-2009-usa_Vertical_Cable_Ladder_System.pdf