Figure 14. The installed
tray should securely bolted with round-headed bolts where lengths or
accessories are attached, that there continuous earth path which
may bonded electrical earth. The most common fin-
ish hot-dipped galvanized but PVC-
coated tray also available. The most common
finish hot-dipped galvanized but PVC-coated tray also available. This type installation
has the advantage flexibility, allowing modifications made speedily
as the need arises. This can only provided in
PVC trunking screened cables are drawn into the trunking. is
used extensively large industrial and commercial installations for sup-
porting and SWA cables which are laid the cable tray and secured
with cable ties through the tray holes.
Cable tray should adequately supported during installation brackets
which are appropriate for the particular installation.
PVC/SWA cable installations
Steel wire armoured PVC insulated cables are now extensively used on
industrial installations and often laid cable tray.
The tray supplied standard widths from 900mm, and wide
range bends, tees and reducers available. The whole tray should provide firm
support for the cables and therefore the tray fixings must capable of
supporting the weight both the tray and cables. 14. 14.
.31 shows factory
made 90° bend The tray can also bent using cable tray bending
machine create bends such that shown Fig.
Definition
Cable tray sheet-steel channel with
multiple holes. used
extensively large industrial and
commercial installations for support-
ing and SWA cables which are laid
on the cable tray and secured with
cable ties through the tray holes.30. The tray should be
bolted the brackets with round-headed bolts and nuts, with the round
head inside the tray that cables drawn along the tray are not damaged.31.
Multi-compartment PVC trunking cannot provide band segregations since
there metal screen between the Bands. The cable has steel wire armouring giving mechanical
Definition
Steel wire armoured PVC insulated
cables are now extensively used on
industrial installations and often laid
on cable tray.30
Segregation cables trunking.
Trunking
lid
Band II
cables
Band I
cables
Band I
cables
FIGURE 14.
When trunking contains rigidly fixed metal barriers along its length, the
same trunking may used enclose cables the separate Bands without
further precautions, provided that each band separated barrier, as
shown Fig.
Cable tray installations
Cable tray sheet-steel channel with multiple holes.Basic Electrical Installation Work
316
When Band circuits are insulated the same voltage Band circuits,
they may drawn into the same compartment
