Noel got in touch with Voltimum because he was unsure about the need for protection for cables installed at a depth of less than 50mm.
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Question:
I heard something today and thought I would ask the question. I understand from the Regs that if a cable is installed in a wall at a depth of less than 50mm it has to be enclosed in metallic protection (i.e. conduit) OR protected by an RCBO. However, an electrician I know was on a job has said that the metallic sheath in FP200 cable is sufficient to not warrant an RCBO, in my opinion, that is doubtful. Can anybody shed any light on this?
Thanks in advance
Noel
Answer:
Richard Atkins, NICEIC, Technical Standards Engineer
Regulation 522.6.202 requires cables to be installed in the safe zones and protected by RCD, indent (i) or in compliance with the installation methods in regulation 522.6.204.
Indent (i) of regulation 522.6.204 states a list of suitable cables. One of the suitable cables stated are cables tested to BS 8439:2011. This type of cable normally has an outer aluminium foil similar to FP200.
Where this type of cable is used it is important to verify from manufacturers information that the cable has been tested to BS 8439 as this standard includes Mechanical and Penetration tests.