It would be impossible to have the wiring system flexibility they need with a conduit wiring system.
Cable tray support spacing nec.
Articles 318 250 and 800 cover various aspects of cable tray systems.
Concurrently nec 392 6 j permits cable tray systems to externally support raceways cables and boxes and conduit bodies as covered by section 314 1 provided that the cable tray is listed and designed for the application.
Cable tray is classified by the nec nfpa 70 the national electrical code as a support system and not as a raceway.
Generally speaking raceway completely encloses the cable inside of it.
Make use of cable tray to support and route the large volumes of cable needed for their operations with a high degree of dependability.
Nema national electrical manufacturers association is an association comprised of the major cable tray.
Large retail and warehouse installations use cable tray to support their data communication cable systems.
If the cable is sized 1 0 awg through 4 0 awg it must be installed in ladder type cable tray with a maximum rung spacing of 9 in.
Nema ve 1 this standard specifies the manufacturing requirements for metal cable trays such as.
Channel cable tray ladder cable tray single rail cable tray wire mesh cable tray solid bottom or nonventillated cable tray and trough or ventilated cable tray and associated fittings for use in accordance with the rules of the national electrical code.
The national electrical code publishes the standards for all types of electrical applications.
Support for the equipment also must be in accord with the appropriate nec article.
Single conductor cable must be 1 0 awg or larger and be permitted to be used in cable tray.