Types of cable Tray Cable Trays - Perforated Cable Trays, Ladder Cable Trays

Electrical > cables tray > Types of cable Tray

Solid Bottom Cable Tray

Ventilated Trough Cable Tray

The only reason to select a ventilated trough cable tray over a ladder type cable tray is aesthetics. No drooping of small cables is visible. The ventilated trough cable tray does provide more support to the cables than does the ladder cable tray but this additional support is not significant. It doesn’t have any impact on the cables service record or life.

Characteristics:

(2) Solid Bottom Cable Tray:

Generally used for minimal heat generating electrical or telecommunication applications with short to intermediate support spans 5 to 12 feet.
The main reason for selecting solid bottom cable tray (with covers) is the concern of EMI/ RFI shielding protection for very sensitive circuits. A solid bottom steel cable tray with steel covers provides a good degree of shielding if there are no breaks or holes in the completed installation.
The solid bottom cable tray system has a disadvantage in that moisture can build up in the cable trays. This can be controlled by drilling 1/4 inch drain holes in the bottom of the cable tray at three foot intervals (at the middle and very near the sides) if the cable tray is not being used for EMI/RFI shielding.
Some engineers and designers specify solid bottom cable trays (often with covers) in the belief that all electrical circuits have to be totally enclosed by metal. The cable trays are just supporting cables that are designed for such installations. Cable failures in cable tray runs rarely happen. Cable failures due to cable support problems in cable trays are non-existent.

Characteristics:

Solid bottom metallic with solid metal covers for non-plenum rated cable in environmental areas
Standard widths of 6, 12, 18, 24, 30 & 36 inches
Standard depths of 3, 4, 5 & 6 inches
Standard lengths of 10, 12, 20 & 24 feet.