Jim asks this question about using a catenary wire strung between buildings to suspend a multicore SWA cable. It has been answered by Prysmian (Theme – Cables, Wiring and Wiring Accessories):
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Question: Is it permissible to install a multicore SWA cable suspended from a catenary wire between buildings?
Whilst, in the Regulations, Table 4A2, Installation Method 35 details ‘Single-core or multicore cable suspended from or incorporating a support wire or harness’ - i.e. a catenary wire, no specific mention is made to the inclusion or exclusion of SWA type cables.
Answer: Our SWA BS 5467 type cable is designed for ‘fixed ridged’ wiring. It is not a flexible cable and, as such, would be unsuitable for continual ‘flexing’.
We are not aware of any regulation that specifically excludes its use in the situation you propose. However, a main concern would be if there is continual motion (swaying for example) producing fatigue strain or abrasion at the end terminations, or against another rigid surface. If this is the case then the method is unsuitable for this cable.
If this method was adopted, I would suggest support to the wire at many close positions (find recommended support spacing’s at www.biconcomponents.co.uk) and provision to mitigate flexing and strain at the terminations.
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