Knockout earth's

[glen.mason]

Hi all,

Where in the regs does it mention @ earth tails being a requirement between sunken knockout box's and the face plate - is there really a need for this, surely the faceplate screws do this job!

 

[padmore12345]

not sure where in the regs but read somewhere, probably on here, you dont have to earth the box if it has one non adjustable lug for the faceplate screws. we all do it cause its good practice. and we all especially enjoy putting an earth cable into a cheap socket it box terminal for it to fall out again instantly when you turn the screw.

 

[Amp David]

Sure its only required if the back box you are using doesn't have a fixed lug on at least one side.

 

[xraytek]

According to 410.3.9 (iii) an exposed conductive part <50mm x 50mm in size does not require protection against fault contact and even gives examples such as screws, rivets and bolts.

That leads me to believe that whether the lugs are adjustable or not there is no requirement to earth the backbox if it is not exposed.

 

[Sintra]

Hi all,

Where in the regs does it mention @ earth tails being a requirement between sunken knockout box's and the face plate - is there really a need for this, surely the faceplate screws do this job!

Where rigid metal conduit or the metal sheath or armour of a cable is used as a protective conductor, a separate protective conductor must connect the earthing terminal of any accessories to the appropriate metal backbox. 543.2.7, 543.7.2.1

 

[Colin Integrale]

[useless reply] : I'm not sure on the regs, but I've been taught to earth metal boxes whatever.

 

[Spudnik]

Where rigid metal conduit or the metal sheath or armour of a cable is used as a protective conductor, a separate protective conductor must connect the earthing terminal of any accessories to the appropriate metal backbox. 543.2.7, 543.7.2.1

Indeed, as this is the only way the accessory would get an earth.

But as for the earthing of back boxes from the faceplate, sometimes i do, sometimes i dont.

 

[sparks1234]

Indeed, as this is the only way the accessory would get an earth.

But as for the earthing of back boxes from the faceplate, sometimes i do, sometimes i dont.

Maybe I will, maybe I wont