tray carrying swa

[davelerave]

is there normally any requirement to bond lengths of tray carrying swa only-

i have to bring a couple of swa's from a sub-board out to 2 exterior air-con units-the tray may not be continuous

thanks

 

[telectrix]

tray is extraneous part of installation. i would link sections with single bond maybe 6mm tagged at supply end. bit unsure if you have to do this with SWA though. better minds than mine may have a better answer.

 

[IQ Electrical]

is there normally any requirement to bond lengths of tray carrying swa only-

i have to bring a couple of swa's from a sub-board out to 2 exterior air-con units-the tray may not be continuous

thanks

Guidance Note 8 Page 151

'Unless the tray introduces a potential that does not already exist in the location in which the system is installed, it will not meet the definition of an extraneous conductive part.
In normal circumstances therefore there is no need to arrange for the conductive parts of the tray to be connected to either a main bonding conductor or any supplementary bonding conductor'

 

[davelerave]

thanks

 

[blackiel]

Bond it...Youre covered then!!!!

 

[IQ Electrical]

Bond it...Youre covered then!!!!

When you explore the wonderful science of bonding, you'll see that it's not just about saving a bit of green/yellow and a couple of lugs, the bonding requirements were revised considerably since the 15th edition of the IEE Regulations to take into account distributed touch voltages under fault conditions.

So it's worth finding out exactly what the requirements are, only then are you 'covered'

 

[olly w]

Guidance Note 8 Page 151

'Unless the tray introduces a potential that does not already exist in the location in which the system is installed, it will not meet the definition of an extraneous conductive part.
In normal circumstances therefore there is no need to arrange for the conductive parts of the tray to be connected to either a main bonding conductor or any supplementary bonding conductor'

I would of thought that cable tray was an exposed conductive part rather than an extraneous conductive part and would require bonding.

It is part of the electrical wiring system and therefore is classed as electrrical equipment!

 

[IQ Electrical]

An exposed conductive part would be the metallic case of say a washing machine etc.

If you read page 151-152 of Guidance Note 8 then all will become clear, it's a really simple principle, complicated by opinion and the 'I'll just bond it anyway' mindset.