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BS 8436 Cable

Hi all I am new to the Forum.


I have a question regarding BS 8436 Compliant Cables. I am aware iof the requirement to protect circuits wired in BS 8436 Cables with "B" Type devices etc due to the requirement to limit fault current in the event of the cable being penetrated by a nail or a screw. However, what if you install the cable clipped direct to the surface and on Cable Tray or basket where the risk of accidental penetration is very low, would it them be acceptable to protect the circuit with "C" Type devices?


I have hunted high and low on the internet for an solution but have failed to find a definitive answer.
Parents

  • Of course it matters what they serve, presumably the connected equipment HAS TO BE protected by a a Type C MCB  because it has an inrush current that would trip a Type B MCB.



    But that's a matter of rating as well as type. A B10 can survive the same inrush as a C6. And a B32 isn't much different from a C20 on the same score. So as long as overload protection isn't critical (or provided downstream) there might be some wiggle room that allows the use of a higher rated B-type instead of a C-type if you really need to stick to the letter of the specification.


      - Andy.
Reply

  • Of course it matters what they serve, presumably the connected equipment HAS TO BE protected by a a Type C MCB  because it has an inrush current that would trip a Type B MCB.



    But that's a matter of rating as well as type. A B10 can survive the same inrush as a C6. And a B32 isn't much different from a C20 on the same score. So as long as overload protection isn't critical (or provided downstream) there might be some wiggle room that allows the use of a higher rated B-type instead of a C-type if you really need to stick to the letter of the specification.


      - Andy.
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