S.W.A. Armour Earthing.

davezawadi (David Stone):

You do try to have competitions sometimes!


As many have said on here many times the sheath should not be considered insulation, it is mechanical protection. The core plastic is insulation, the bedding layer is not, just packing, so the armour is an exposed conductive part even if sheathed. is plastic-coated metal trunking or conduit an exposed conductive part? Yes, because unlike the cores it is not insulation tested with a water bath at manufacture, and whatever YOU do, may have defects you have not noticed. Is this part of an EICR, because this should be a code 2, but is obviously easily fixed with a new metal gland etc. The plastic hoods over glands are not insulation, they can easily be pulled back, they are environmental protection for the armour.

The black outer S.W.A. covering is an electrical insulator. If people want to tamper with shrouds then that is wrong and could be dangerous. They are not that easy to pull back, they are a pig to put on most times-a very tight fit.  We can't excuse people tampering and dismantling electrical equipment. They are taking a risk.


The reason for the question is this:


I came upon a long length of 2.5mm2 3 core S.W.A. running through trees at high level and out of reach recently. The supply was TT. The cores were connected as L. N. and C.P.C. The armouring was not connected at each end, just left disconnected at plastic enclosures.


 I alerted the site owners of the defect, then began to wonder about which regs. actually apply here.


The outer sheath of S.W.A. cable is made of P.V.C. a well known electrical insulator. So the steel armour is not exposed.

cab_6943x_1.pdf (electricalcounter.co.uk)


Z.

 

davezawadi (David Stone):

You do try to have competitions sometimes!


As many have said on here many times the sheath should not be considered insulation, it is mechanical protection. The core plastic is insulation, the bedding layer is not, just packing, so the armour is an exposed conductive part even if sheathed. is plastic-coated metal trunking or conduit an exposed conductive part? Yes, because unlike the cores it is not insulation tested with a water bath at manufacture, and whatever YOU do, may have defects you have not noticed. Is this part of an EICR, because this should be a code 2, but is obviously easily fixed with a new metal gland etc. The plastic hoods over glands are not insulation, they can easily be pulled back, they are environmental protection for the armour.

The black outer S.W.A. covering is an electrical insulator. If people want to tamper with shrouds then that is wrong and could be dangerous. They are not that easy to pull back, they are a pig to put on most times-a very tight fit.  We can't excuse people tampering and dismantling electrical equipment. They are taking a risk.


The reason for the question is this:


I came upon a long length of 2.5mm2 3 core S.W.A. running through trees at high level and out of reach recently. The supply was TT. The cores were connected as L. N. and C.P.C. The armouring was not connected at each end, just left disconnected at plastic enclosures.


 I alerted the site owners of the defect, then began to wonder about which regs. actually apply here.


The outer sheath of S.W.A. cable is made of P.V.C. a well known electrical insulator. So the steel armour is not exposed.

cab_6943x_1.pdf (electricalcounter.co.uk)


Z.