Assembly & installation
Cable routing and containment
The right cable type, conduit, trunking and fire stopping
The cable routes determine whether the cables can carry their load, whether they can be replaced, and whether they meet the fire requirements. The choice of cable type and route must suit the environment the circuit passes through.
Choose the cable type according to the environment
Choose the cable type according to where the cable is run: NYM-J for fixed indoor installation, NYY-J for burial and damp/outdoor environments, and halogen-free NHXMH in fire-classified buildings and escape routes.
Plan the cable route
Fix the cable route before you pull: concealed in conduit (e.g. M20) for replaceability, or surface-mounted in trunking (e.g. 40×25 mm) in commercial premises. Avoid unnecessary kinks and keep an even radius, so the cable is not damaged.
Size conduit and trunking for the conductors
The size of the conduit and trunking is chosen according to the number and cross-section of the conductors to be run in it. There must be room for the cables to be pulled out and replaced — that is the whole point of a conduit.
Allow for the effect of the installation method on current-carrying capacity
The cable's current-carrying capacity (IZ) depends heavily on the installation method. Cables grouped in bundles or conduit and high ambient temperature reduce IZ via correction factors (Kt and Ks). Look up the figures in DS/HD 60364-5-52 and the calculator — never guess.
Kttemperature correction (> 30 °C)Ksgrouping reduction (bundle/conduit)Fire-sealed penetrations
Where cables or pipes pass through fire-rated walls and floor separations, the penetration must be fire-stopped so that the fire resistance is maintained. Also check the choice of cable at penetrations as part of the inspection.
Label and finish correctly
Label the circuits, cut the cables cleanly in boxes and board, and keep to the harmonised conductor colours. A tidy installation makes both verification and later fault-finding easier.
Leave a little extra cable length in boxes and the board — it makes reconnections and repairs much easier.
Source
Based on DS/HD 60364-5-52 (installation methods and current-carrying capacity) and the trade's product range (conduit, cable trunking) and template »new domestic installation«.
Videos from NDLA
Video guide· Norwegian speech
Skjult installasjon, trekking
Source
NDLA
«Skjult installasjon, trekking» · Creator: Esteban Panza
License: CC BY-SA 4.0 · Original at NDLA ↗
Shown unaltered in the original language with the source's own subtitles. The video shows Norwegian practice — the method is often the same, but rules and standards may differ from the Danish ones.