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Simon Storage, Fluorobenzene Gantry / Tank 24
Instrument & Electrical Installation Tender Package
DOCUMENT REF: SI347001.INS
ISSUE: B DATE: 13.10.97
PAGE: 9 OF 23
2.9.2
Installation
(Cont.)
Cable joints shall not be used unless specified or on the written authority of the Engineer.
Cores shall be marked to comply with the references given in the cable schedules using
Critchley Z type or equivalent. They shall be identified having black characters reading
from the terminals outwards. Clip-on ferrules will
not
be accepted.
Insulated cables shall have standard Hawke compression CW type gland of the appropriate
size. EEx 'd' glands to be used on EExd equipment. EEx 'e' glands to be used for I.S. cables
and EEx’e’ equipment.
Each gland shall be bonded to its cable armouring, where applicable and unless otherwise
specified, and to be complete with earth tag and locknut.
Each gland shall be fitted with a PVC slip-over shroud, unless otherwise agreed with the
Engineer.
Cables shall be protected against mechanical damage at vulnerable points. This particularly
applies in exposed locations where cables emerge from ground or floor.
2.9.3
Cables in Ground
When excavating trenches for underground cables, due account shall be taken of ground
conditions. Cables in normal ground shall be laid in trenches 500mm deep minimum
unless agreed otherwise. Before any excavation starts, the Contractor shall check if there is
any record of other underground services along the route.
Trench bottoms shall be cleared of irregular and sharp objects before applying bedding.
Cables shall be laid the appropriate distance apart (dictated by rating factors) on a bed of
clean, dry, builders' sand, 75mm deep.
Cables shall be blinded with a similar layer as soon as possible after installation.
The trench shall be backfilled a further 150mm with riddled, excavated spoil.
Interlocking cable tiles or continuous marker tape, giving clear warning or danger, shall be
placed over each cable or closely associated groups of cables.
Backfill to surface shall be allowed to settle before final topping and grading.
Approved route markers shall be installed where cables enter of leave buildings, at changes
of direction and at appropriate intermediate intervals.
Pilot cables shall run continuously with their associated main cable, where the route is
common.