Earthing braid of SY and CY cable

This Q & A is one of thousands posted in our Technical Expertise area, and answered by our Voltimum Experts.

Question:

There are lots of questions and answers about SY and CY cables but nothing seems to state if the braiding should be earthed - by that I mean not used as an earth.

It appears to be that if the cable passes through an insulated gland and the braiding at the ends is insulated, (i.e. cannot be touched) then no earthing is required. Is this correct?

Answer:

Gary Parker

Most manufacturers state that the galvanised steel wire braid is used to prevent interference i.e. it is used as a screen.  In order for this to be used as a screen, it must be connected to the earthing system.

Most manufacturers would recommend the braid be connected to earth as standard. It is fair to say that the braid isn't suitable to be used as a cpc.  

If it is connected to earth, then you will always screen the cable.