Use of an earthing rod

[bazbazbaz]

Just putting in some bollard lights that obviously require earthing. Got a strange issue.

The feed to the armoured cable that feeds the lights from the switch inside is standard 3 cable earthed. That cable feeds two of the lights that will be replaced shortly. But after the second light, the previous fitter has run simple 2 core armoured cable with no earth to the next light in the string. That light is being replaced and all further lights from that point will be fed with new 3 core armoured cable.

So I basically have a 10 foot length of cable in the middle of the system with no earth wire. Therefore no onward earth. And guess what, it’s directly under the patio which is not being replaced.

So the question is, can I simply introduce an earthing rod at the end of the two core cable which will then earth the remaining lights on that part of the circuit. Or do I need to rip up the patio and replace that 10ft length of cable?

The general system is fed with TN-S earth.

Any thoughts?

 

[Fleeting]

Use the armour as the cpc. Even though a separate core is predominantly used as a cpc this armour must be earthed so therefore is can be used.

 

[bazbazbaz]

Oh man. Of course. Great answer. Thanks.

 

[Andy™]

Even though a separate core is predominantly used as a cpc

usually by those who only work on single phase and think a core must be used as an earth and dont know otherwise... other than that, its almost always the armour as the cpc (except in certain situations where you need a core as a cpc for Zs etc)

 

[Fleeting]

Armour as a cpc, ARE YOU CRAZY.

 

[Andy™]

ARE YOU CRAZY.

think we all know the answer to that

 

[Murdoch]

I guess the question now is can a proper connection be made to the cables concerned

And don't forget to check the R1 + R2 before you energise

 

[steptoe]

The mind boggles

 

[kerching]

Surely this is a wind up?
NOT knowing the SWA is used as a cpc??? Surely this is taught nowadays.

I use a lot of 5 core ( 4 core and earth SWA ) as it suits me for what I do, some may disagree. Deal with it

Just saying

 

[SPECIAL LOCATION]

Just putting in some bollard lights that obviously require earthing. Got a strange issue.

The feed to the armoured cable that feeds the lights from the switch inside is standard 3 cable earthed. That cable feeds two of the lights that will be replaced shortly. But after the second light, the previous fitter has run simple 2 core armoured cable with no earth to the next light in the string. That light is being replaced and all further lights from that point will be fed with new 3 core armoured cable.

So I basically have a 10 foot length of cable in the middle of the system with no earth wire. Therefore no onward earth. And guess what, it’s directly under the patio which is not being replaced.

So the question is, can I simply introduce an earthing rod at the end of the two core cable which will then earth the remaining lights on that part of the circuit. Or do I need to rip up the patio and replace that 10ft length of cable?

The general system is fed with TN-S earth.

Any thoughts?

Don't think I quite understood how you were proposing to ensure you meet your disconnection times, max Zs on the lights that are using your new simple proposed earth rod?

 

[kerching]

I don't get the "obviously require earthing" statement. Without reading the MIs how can WE confirm this? Is it because they re metal? A lot of metal lights are Class II. However the CABLE needs an earth . The SWA is not just for mechanical protection