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TECHNICAL INFORMATION
Technical information
p202
&
204
Product
Information
PVC–U domestic and general trunking
| 303
Material
PVC-U is flame retardant and self-
extinguishing. It provides a 100%
recyclable material with good
sustainability.
Installation
Positioning
Feeder or distribution trunking.
Expansion/contraction
PVC-U expands and contracts at a
uniform rate of approx 5.25mm in
a 3 metre length for a temperature
change of 25°C. Therefore, a 3mm gap
between each length of trunking base
is recommended. Fittings allow for
thermal expansion of the covers.
Fitting
• Secure trunking base in one plane
only every 500mm by drilling
alternate 6mm holes.
• Use roundhead screws.
• Avoid over-tightening to permit
thermal movement.
• The use of plastic caps over screw
heads is recommended to protect
installed cables.
• To provide cable segregation,
dividing fillets are snapped on to
internal nibs in base.
• To cut the trunking, use a fine-
toothed panel or power jig-saw.
• External profile fittings overlap joints
by up to 10mm to cover cutting
inaccuracies.
• A variable angle jig-saw or chop
saw is recommended for cutting 45°
mitres.
•
Maxi only:
trunking lengths are
connected using internal couplers as
follows:
• Cement one end of the internal
coupler to one base using adhesive
solvent MSC. Leave other end of
coupler free in adjoining base to
facilitate thermal movement.
Single lengths
Where it is required to fit a single
length of trunking (under 3 metres)
between two inside walls and no
accessory box is fitted, it is advisable to
install a coupler in the centre of the run
to facilitate the removal of the cover.
Joints and bends
• Clip-on fittings and 2-part moulded
flat angle: base must be mitred at
45˚ to ensure total enclosure of
trunking, including any internal fitted
segregator.
• Fabricated fittings: a 3mm gap
between trunking base and bend or
flat angle is recommended.
• External moulded fittings overlap the
joints by up to 10mm to cover
cutting inaccuracies.
• Maxi fabricated fittings are supplied
with internal couplers (see Fittings)
• Secure end caps using solvent
adhesive MSC3.
Accessories
•
Sceptre DTR1, Maxi MTRS100/50
and MTRS100:
accessory boxes and
plates can be used.
• Remove appropriate knockout and
clip box into base.
•
Sceptre DTR2:
only accessory plates
can be used.
• When boxes or plates are installed
consecutively, fit a 25mm cover
spacer (MTRS100LID25WH) between
the accessories to conceal space
between the boxes.
Covers
Covers are designed to limit
unauthorised removal and to remain
in position during normal conditions
irrespective of impact and minor
undulations of the mounting surface.
Covers – fitting
Covers are clipped into place from
front. If accessory boxes are installed,
the cover is butt-joined to the edge
of the box. Cut edges of the cover
are concealed by the accessory. For
external fitting couplers, the following
gaps should be left between the two
cover ends to permit the fitting to clip
to base:
DTR2
20mm
MTRS50
20mm
MTRS75
20mm
MTRS75/50
20mm
MTRS100/50
20mm
MTRS100
30mm
DTR1:
DTR1 couplers are held in
place by the two covers. To install,
slide coupler up against first installed
cover. Fit adjoining cover and slide
up to coupler, ensuring the coupler
moulding extends over the two covers.
Covers removal
To remove a cover, first detach a
coupler or internal/external bend to
gain access. The main cover can then
be gently eased off the base.
Lid in
position
Lid
removed
Coat this
end with
silicone
grease
Internal
Coupler
Secure this end of
the coupler with
solvent adhesive
50mm Min
500mm
50mm
500mm
Maxi and Sceptre trunking
– continued