The cabling is considered as the installation of the cable connection between different equipment and plants. These are the requirements for cable installation:
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Cable must be flame resistant, suitable for the environment
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Mud resistive where cables need to be routed through mud/oil
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Cable segregation should be done precisely.
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Multi-core cables with collective screens must be standard, individual screens must be used only when necessary.
Cable routing:
Cable routing is the process of installing cable through the possible shortest path. The cables can be routed through cable ladders and cable trays.
Otherwise, cable conduits are used in special purposes which allows mechanical protection for cables, but only for shorter distances. Where conduits are used, they shall be installed with open ends.
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There are computer-based cable routing design system which represents the main cable support system, represented by ladder segment references, transit numbers etc.
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The cable tray should not hold many number of cables such that the height of cables should not exceed the height of the tray.
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Redundant cable systems shall be routed separately.
Cable installation:
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Once a cable has been cut, a protective cap/seal will be applied at the end, when exposed to a humid atmosphere.
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All cable entries and out to equipment located outdoor must be from downside, top entries are not allowed.
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Side entries are allowed, but only provided with drip nose.
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Sufficient spare cable must be provided for equipment that needs future adjustments. Otherwise, the equipment must be disassembled for maintenance and calibration without disconnecting the cable.
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For equipment installed in hazardous areas, the braid shall be earthed at the hazardous end. When using single core cables, additional cables for earthing have to be installed.
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Single core cables should not be installed separately through openings surrounded by magnetic materials.
Cable Segregation:
Horizontally installed cable ladders must have sufficient space to facilitate towing and rope lashing / securing, minimum clearance of 300 mm between the top of a ladder to the bottom of the next edge of the ladder and from the edge of the ladder. the upper staircase to the ceiling.
Instrument cables that are non IS and IS must be routed on the same ladders/cable trays. If they are routed in the same ladder/tray, the IS and Non-IS cables, which contain both armor and screen, can be joined in the same package