Cable Tray Installations & Trunking
According to the National Electrical Code (NEC), a cable tray is a unit connected to fittings, creating a rigid structural system used to support cables and raceways. They are particularly beneficial in conditions where changes to a wiring system are anticipated, since new cables can be installed by laying them in the tray, instead of pulling them through a pipe.
However, when cable tray system has been installed suitably in a project, following advantages can be counted:
- Cable tray system enhances safety of electrical wiring system.
- Cable tray installation provides reliability in any circumstances.
- Cable tray system saves spaces, materials, labour, time and costs.
- Maintenance and extension of cable tray installation are easier than any other wiring system.
Equipment’s needed for installation of cable trays and trunking:
- Open and box spanners
- Wire cutters
- Drill machine
- Flat file
- Base Cutter
- Measuring tape
- Screw drivers
- Wooden hammer
Method Statement For Installation Of Cable Tray & Trunking
1. Before commencing installation in any given area, examining all parts of the area is recommended. Should any condition be found which will prevent the proper implementation of the work, installation will not continue in that area until such conditions are corrected by the contractor.
2. When transporting materials, they must be handled with care and lowered carefully to the ground. They should never be dropped.
3. Cable tray and trunking should be stored on site where cover in dry, and well ventilated storage facilities.
4. Materials required for the installation should be delivered to the site ahead of time and the right equipment should be used to lift the materials for example, crane. However, only materials required for installation should be moved to the site and those not needed should be kept separately, in order to enable adequate working space.
5. The cable tray should be installed with a 40mm minimum space between the structure and the tray.
6. The cable tray bracket and ladder should be trimmed to required size as well as galvanising paint should be applied on the edges.
7. Any cutting on the cable tray should be done in a solid area and not across the perforation of the cable tray. Burrs needs to be removed and cuts need to be protected with anti-rust galvanised paint. Where all cutting sections are available, and they should be free from sharp edges.
8. The fitting used should comply to manufacturer specifications in the installation of trays and trunking.
9. A very strong ladder rack should be used for all heating ventilation cables within the building substation.
10. Cable trays & ladders should not be install below water/sewage pipes.