Flexible cables used as fixed wiring

Question

Hi All 
 Is there anything in the regs that would prohibit the use of flexible cables (H07) as part of a fixed installation. (Surface and sunken)

AJJewsbury · Accepted Answer

Not these days. Back in the 15th Ed and before there was an explicit ban on using flexes for fixed wiring other than a few exceptions and that seems to have remained in the collective memory surprisingly well. These days the requirement is basically the same as for rigid cables - must be suitable for the conditions and generally meet BS 7671 requirements (see 521.9). Heavy duty flex (which H07 is likely to be) is likely to be OK in the majority of circumstances. The only other consideration is that flex generally has a lower CCC than rigid of the same nominal c.s.a. by a small margin (3-5%) so a small adjustment of some calculations might be needed (see appendix 4, 2.4) but that's a long way from a prohibition. 
 - Andy.

gkenyon · Answer

AJJewsbury said: Not these days. 
 Agreed, there are some provisos as Andy has said, and cable to be selected to an appropriate Duty for the application. Some good comments in this thread to help out: engx.theiet.org/.../wiring-on-fixed-installation-with-class-5-conductor-flexible-cable

Flexible cables used as fixed wiring

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