Sy cable question

[nathansinar]

Hi guys new to the forum and will introduce myself shortly

I have attached an image of a spur i have taken as you can see from the attached image

I am doing a trainee maintenance engineer role and just wanted some info on the below.

1.) when using sy cable do you have to earth the sheeth? i have had various reponses saying it is good practice but you can get away with using the cpc inside the cable and that alone?

2.) in the image i have posted becuase the sheeth hasnt been used an earth from the the spur to what ever it is feeding, does an earth need adding from the back of the spur plate to actual spur box as it could become live?? is it a reg that this needs to be done?

Thanks for help!

Nathan

 

[nathansinar]

The braid should be earthed as its intended use is primary a control cable and the braid is used as a shield for electromagnetic interference. VSDs can give off a lot of interference which interfere with metal detectors and other sensitive equipment. The braid can be earthed at one end or both for higher frequencies.
That said the cable is often used as a rough service cable and often used as you have. the problem is widespread (I have used it in the past)
The worst electric shock I have had was from this type of cable the braid was not earthed and used as a trailing cable on a farm. A dog yelped as it walked on a board off a pallet. So suspecting a nail in the wood I picked it up touching the damaged cable which was live. my feet and hands were wet and I felt it hard.

but you can get away with it thats all im saying im not saying its the best way by any means haha

 

[Jamchiv01]

Just because you see other people do it, doesn't mean its the right thing to do

 

[nathansinar]

im just stating from what i have seen in the past i have seen it d

Just because you see other people do it, doesn't mean its the right thing to do

and it doesnt mean its the wrong thing to do ,as i have said i agree the way you showed is a better method but the way i have done it as regards of not earthing the braid is not breaking a reg that was my only point lol

and cheers for your help mate

 

[Wilko]

and sy can be used for fixed purposed i have seen it done in loads of place when i was an apprentice in another job, people have diffrent views yes swa is a lot tougher and people would say " better fit for purpose " but it can still be used all the wise every install i have seen must be crap and they cant all be wrong

Hi - please don't think that I'm saying all SY installations must be bad, not at all. And people can and do use it. But seeing a manufacturer state their SY cable is not approved under BS7671 for fixed wiring gave me pause for thought. What would be the result of a future EICR ?

 

[Barry White]

The problem here is the manufacturers some state control cable only some state its an armoured cable
see | RS Pro SY Control Cable, 6 Core, Polyvinyl Chloride PVC Sheath , 1.5 mm² CSA | - http://uk.rs-online.com/web/p/sy-cable/0522597/
Type SY
The RS SY cable combines the characteristics of a flexible mains cable with that of a steel wire armoured type and is suitable for fixed installations or for flexible use in conditions of light mechanical stress.

then see | RS Pro SY Control Cable, 5 Core, Screened Polyvinyl Chloride PVC Sheath , 6 mm CSA | - http://uk.rs-online.com/web/p/sy-cable/8274215/ SY control cables are not suitable for fixed wiring applications requiring compliance with the requirements set out in BS7671.

I think it was Westwood10 who said you would not get a definitive answer and I agree.

Common sense should prevail here fit the cable best suited for the conditions.

 

[nathansinar]

Oc not wilko i feel as if ive made a bit of a donkey of msyelf on here lol???

I completely agree with you im just saying it was a spur i took of the socket in that image whlst being assited by another spark at our place and when i raised the subject i was told you can use plastic glands and you can leave the braid as i have? im certainly not saying its the best way but it can be done like that

 

[Risteard]

Why are you asking if you have already decided what the answer is?

 

[nathansinar]

Thanks for all the feedback anyway guys it is appreciated.

 

[Darkwood]

The braid if used on low voltage cabling must be earthed, consider a conductive object pierces the cable into the phase only, it would make the whole of the braiding live, where the regs state it should not be used as a power cable it refers to using it as tails but since the latest amendment it is no longer recognised to meet BS standards for general use, if anyone users this stuff and does not earth the braid and yet they class themselves as competent then they really want to question their knowledge.. its a braid or a screen and can be used for low voltage but you have to know when and why it can before you do, the numpties that tell you it's ok without earthing of the braid are questionable about their competence to be electricians considering it can kill if not earthed.

 

[nathansinar]

Im just saying ive seen intances where the braid has not been earthed at all in many places i have worked and been in. i dont disagree with you at all, i just see so many different views and im not one to argue with people who have done it i guess people have different prefrences.

 

[Darkwood]

It wasn't a dig at you, you had the intellect to resource the info and ask others so I respect you for that, just worried about your work mates though teaching you very dangerous practices...

We all climb the learning ladder and you strike me as one who will question what he doesn't understand or agree with and find out, you remind me of me at your stage in this career so given that, I know you'll go far

This is what the forum is for so don't be afraid to ask similar questions.

PS it not a preference issue here it's the safety of the installation and the users hence my strongly worded post.

 

[nathansinar]

Thanks mate and yeah i am like that and until the day comes when i know everything *pun ...ill be the same.

My main issue is confidence and being afraid to ask or fear of doing something wrong. im 23 wanna do my level 3 qual and just become good at what i do. im never happy i always want better but hope to ask many more questions on here along the way

Nath

 

[westward10]

Im just saying ive seen intances where the braid has not been earthed at all in many places i have worked and been in. i dont disagree with you at all, i just see so many different views and im not one to argue with people who have done it i guess people have different prefrences.

 

[westward10]

The braid if used on low voltage cabling must be earthed, consider a conductive object pierces the cable into the phase only, it would make the whole of the braiding live, where the regs state it should not be used as a power cable it refers to using it as tails but since the latest amendment it is no longer recognised to meet BS standards for general use, if anyone users this stuff and does not earth the braid and yet they class themselves as competent then they really want to question their knowledge.. its a braid or a screen and can be used for low voltage but you have to know when and why it can before you do, the numpties that tell you it's ok without earthing of the braid are questionable about their competence to be electricians considering it can kill if not earthed.

That is rather scathing, can you provide any documentation which states the braid is to be earthed for LV applications. Then perhaps you can issue it to the trade to safe further confusion.

 

[nathansinar]

That is rather scathing, can you provide any documentation which states the braid is to be earthed for LV applications. Then perhaps you can issue it to the trade to safe further confusion.

What are you saying mate? im just gonna re ask the question at work today most people are saying its a must do sorry if you mean the same , just trying to understand your post
Cheers