Steel conduits and trunking are,
however, much heavier than single cables and, therefore, need substantial
and firm fixings and supports.4) and shown Table 14.
For the most robust fixing masonry materials expansion bolt such as
that made Rawlbolt should used.
FIGURE 14.8. 14.32
Same manufactured girder supports for electrical equipment.The conduit, effect, replaces the PVC outer sheath of
a cable, providing mechanical protection for the insulated conductors.Basic Electrical Installation Work
320
masonry nail which means that the cables can fixed wood, plaster or
brick with almost equal ease.
For lightweight fixings hollow partitions plasterboard spring toggle
can used.5. con-
duit installation can rewired easily altered any time and this flexibil-
ity, coupled with mechanical protection, makes conduit installations popular
for commercial and industrial applications.
When heavier more robust fixing required support cabling or
equipment nut and bolt screw fixing called for.
Let look little more detail individual joining, support and fixing
methods.
Cables must run straight and neatly between clips fixed equal distances
and providing adequate support for the cable that does not become
damaged its own weight (IEE Regulation 522. wide range support brackets available
for fixing conduit, trunking and tray installations the fabric commer-
cial industrial installation. Wood screws may be
screwed directly into wood but when fixing stone, brick concrete is
first necessary drill hole the masonry material which then plugged
with material (usually plastic) which screw can secured.
.
A commercial industrial installation might call for conduit trunking
wiring system. conduit tube, channel pipe which insulated con-
ductors are contained. Some these are shown Fig. Plasterboard cannot support screw fixing directly into itself
but the spring toggle spreads the load over larger area, making the fixing
suitable for light loads.32
